diff --git a/apps/api/src/global-types/classroom-role.enum.ts b/apps/api/src/global-types/classroom-role.enum.ts
index 106626e..a7ff1ca 100644
--- a/apps/api/src/global-types/classroom-role.enum.ts
+++ b/apps/api/src/global-types/classroom-role.enum.ts
@@ -4,7 +4,6 @@ export enum ClassroomRole {
   OWNER = 'OWNER',
   STUDENT = 'STUDENT',
   INSTRUCTOR = 'INSTRUCTOR',
-  TA = 'TA',
 }
 
 registerEnumType(ClassroomRole, {
diff --git a/apps/api/src/modules/classroom/classroom.service.ts b/apps/api/src/modules/classroom/classroom.service.ts
index 2cb4a52..f0f13b8 100644
--- a/apps/api/src/modules/classroom/classroom.service.ts
+++ b/apps/api/src/modules/classroom/classroom.service.ts
@@ -16,7 +16,7 @@ export class ClassroomInviteCodeGenError extends Error {
 
 @Injectable()
 export default class ClassroomService {
-  constructor(private prismaService: PrismaService) { }
+  constructor(private prismaService: PrismaService) {}
 
   async getUserClassrooms(user: User) {
     return this.prismaService.classroom.findMany({
@@ -32,7 +32,7 @@ export default class ClassroomService {
 
   getMemberInAction(classroomId: string, userId: string) {
     return this.prismaService.classroomMember.findUnique({
-      where: { classroomId, userId },
+      where: { classroomId_userId: { classroomId, userId } },
     })
   }
 
@@ -125,63 +125,51 @@ export default class ClassroomService {
     classroomId: string,
     userId: string,
     memberId: string,
-    role: ClassroomRole) {
-
+    role: ClassroomRole
+  ) {
     //get user from the classroom
-    const memberInAction = this.getMemberInAction(classroomId, userId)
+    const memberInAction = await this.getMemberInAction(classroomId, userId)
 
     //check if user exists in the classroom
     if (!memberInAction) {
-      throw new UserInputError(
-        'You are not a member of this classroom'
-      )
+      throw new UserInputError('You are not a member of this classroom')
     }
 
     //check if user is owner of the classroom
     if (memberInAction.classroomRole !== ClassroomRole.OWNER) {
-      throw new UserInputError(
-        'You are not the owner of this classroom'
-      )
+      throw new UserInputError('You are not the owner of this classroom')
     }
 
     //get member from the classroom
     const ifMemberExist = await this.prismaService.classroomMember.findUnique({
-      where: { classroomId, userId: memberId },
+      where: { classroomId_userId: { classroomId, userId: memberId } },
     })
 
     //check if member exists in the classroom
     if (!ifMemberExist) {
-      throw new UserInputError(
-        'This user is not a member of this classroom'
-      )
+      throw new UserInputError('This user is not a member of this classroom')
     }
 
     //update member role
     return this.prismaService.classroomMember.update({
-      where: { classroomId, userId },
-      data: { classroomRole: role },
+      where: { classroomId_userId: { classroomId, userId } },
+      data: { classroomRole: { set: role } },
     })
   }
 
-  async removeMember(
-    classroomId: string,
-    userId: string,
-    memberId: string) {
-
+  async removeMember(classroomId: string, userId: string, memberId: string) {
     //get member who tries to remove someone from the classroom
-    const memberInAction = this.getMemberInAction(classroomId, userId)
+    const memberInAction = await this.getMemberInAction(classroomId, userId)
 
     //check if member exists in the classroom
     if (!memberInAction) {
-      throw new UserInputError(
-        'You are not a member of this classroom'
-      )
+      throw new UserInputError('You are not a member of this classroom')
     }
 
     //check if any member tries to remove himself
     if (memberInAction.userId === memberId) {
       return this.prismaService.classroomMember.delete({
-        where: { classroomId, userId: memberId },
+        where: { classroomId_userId: { classroomId, userId: memberId } },
       })
     }
 
@@ -195,20 +183,20 @@ export default class ClassroomService {
 
     //get member who is being removed from the classroom
     const memberToRemove = await this.prismaService.classroomMember.findUnique({
-      where: { classroomId, userId: memberId },
+      where: { classroomId_userId: { classroomId, userId: memberId } },
     })
 
     //check if memberToRemove exists in the classroom
     if (!memberToRemove) {
-      throw new UserInputError(
-        'This user is not a member of this classroom'
-      )
+      throw new UserInputError('This user is not a member of this classroom')
     }
 
     //check if instructor tries to remove owner
     //instructor is not allowed to remove owner
-    if (memberToRemove.classroomRole === ClassroomRole.OWNER
-      && memberInAction.classroomRole === ClassroomRole.INSTRUCTOR) {
+    if (
+      memberToRemove.classroomRole === ClassroomRole.OWNER &&
+      memberInAction.classroomRole === ClassroomRole.INSTRUCTOR
+    ) {
       throw new UserInputError(
         'You are not allowed to remove the owner of the classroom'
       )
@@ -216,8 +204,10 @@ export default class ClassroomService {
 
     //check if instructor tries to remove another instructor
     //instructor is not allowed to remove another instructor
-    if (memberToRemove.classroomRole === ClassroomRole.INSTRUCTOR
-      && memberInAction.classroomRole === ClassroomRole.INSTRUCTOR) {
+    if (
+      memberToRemove.classroomRole === ClassroomRole.INSTRUCTOR &&
+      memberInAction.classroomRole === ClassroomRole.INSTRUCTOR
+    ) {
       throw new UserInputError(
         'You are not allowed to remove any instructor of the classroom'
       )
@@ -225,7 +215,7 @@ export default class ClassroomService {
 
     //remove member from the classroom
     return this.prismaService.classroomMember.delete({
-      where: { classroomId, userId: memberId },
+      where: { classroomId_userId: { classroomId, userId: memberId } },
     })
   }
 
diff --git a/apps/api/src/modules/competition/competition.module.ts b/apps/api/src/modules/competition/competition.module.ts
index 6a4789e..93bd819 100644
--- a/apps/api/src/modules/competition/competition.module.ts
+++ b/apps/api/src/modules/competition/competition.module.ts
@@ -1,12 +1,10 @@
 import { ModelsModule } from '@aelp-app/models'
 import { Module } from '@nestjs/common'
-import CompetitionResolver from './competition.resolver'
 import CompetitionService from './competition.service'
 
 @Module({
   imports: [ModelsModule],
   providers: [
-    CompetitionResolver,
     CompetitionService
   ],
 })
diff --git a/apps/api/src/modules/competition/competition.service.ts b/apps/api/src/modules/competition/competition.service.ts
index 7dabb7e..e0eeca6 100644
--- a/apps/api/src/modules/competition/competition.service.ts
+++ b/apps/api/src/modules/competition/competition.service.ts
@@ -6,19 +6,23 @@ import { User } from '../user/types/user.model'
 
 @Injectable()
 export default class CompetitionService {
-  constructor(private prismaService: PrismaService) { }
+  constructor(private prismaService: PrismaService) {}
 
   async createCompetition(data: CreateCompetitionInput, user: User) {
-
     return this.prismaService.competition.create({
       data: {
-        ...data,
+        isPrivate: data.isPrivate,
+        assessment: { connect: { id: data.assessmentId } },
         creatorUser: { connect: { id: user.id } },
       },
     })
   }
 
-  async updateCompetition(id: string, data: CreateCompetitionInput, user: User) {
+  async updateCompetition(
+    id: string,
+    data: CreateCompetitionInput,
+    user: User
+  ) {
     const competition = await this.prismaService.competition.findUnique({
       where: { id },
     })
@@ -29,7 +33,7 @@ export default class CompetitionService {
 
     return this.prismaService.competition.update({
       where: { id },
-      data: { data },
+      data,
     })
   }
 
@@ -75,8 +79,10 @@ export default class CompetitionService {
 
     return this.prismaService.competitionParticipant.delete({
       where: {
-        competitionId: competition.id,
-        userId: user.id,
+        competitionId_userId: {
+          userId: user.id,
+          competitionId: competition.id,
+        },
       },
     })
   }
@@ -94,5 +100,4 @@ export default class CompetitionService {
       },
     })
   }
-
 }
diff --git a/apps/api/src/modules/competition/types/create-competition-input-type.ts b/apps/api/src/modules/competition/types/create-competition-input-type.ts
index 4faed14..ef3dcad 100644
--- a/apps/api/src/modules/competition/types/create-competition-input-type.ts
+++ b/apps/api/src/modules/competition/types/create-competition-input-type.ts
@@ -1,11 +1,10 @@
 import { InputType, Field } from '@nestjs/graphql'
-import { Assessment } from '../../assessment/types/assessment.model'
 
 @InputType()
 export class CreateCompetitionInput {
-  @Field()
-  isPrivate!: string
+  @Field(() => Boolean)
+  isPrivate!: boolean
 
-  @Field({ nullable: true })
-  assessment?: Assessment
+  @Field(() => String, { nullable: true })
+  assessmentId?: string
 }