diff --git a/app/api/schema/sessions.py b/app/api/schema/sessions.py
index 443dd3cf68..ee9e833f1a 100644
--- a/app/api/schema/sessions.py
+++ b/app/api/schema/sessions.py
@@ -33,7 +33,8 @@ class Meta:
 
     @validates_schema(pass_original=True)
     def validate_fields(self, data, original_data):
-        if 'id' in original_data['data']:
+        is_patch_request = 'id' in original_data['data']
+        if is_patch_request:
             try:
                 session = Session.query.filter_by(id=original_data['data']['id']).one()
             except NoResultFound:
@@ -54,9 +55,9 @@ def validate_fields(self, data, original_data):
                     {'pointer': '/data/attributes/ends-at'},
                     "ends-at should be after starts-at",
                 )
-            if datetime.timestamp(data['starts_at']) <= datetime.timestamp(
-                datetime.now()
-            ):
+            if not is_patch_request and datetime.timestamp(
+                data['starts_at']
+            ) <= datetime.timestamp(datetime.now()):
                 raise UnprocessableEntity(
                     {'pointer': '/data/attributes/starts-at'},
                     "starts-at should be after current date-time",