diff --git a/iOSClient/Login/NCLogin.swift b/iOSClient/Login/NCLogin.swift
index 2ff7d11ade..6b53155078 100644
--- a/iOSClient/Login/NCLogin.swift
+++ b/iOSClient/Login/NCLogin.swift
@@ -191,6 +191,8 @@ class NCLogin: UIViewController, UITextFieldDelegate, NCLoginQRCodeDelegate {
                 return outgoing
             }
         }
+        
+        NCNetworking.shared.certificateDelegate = self
     }
 
     override func viewDidAppear(_ animated: Bool) {
@@ -493,7 +495,9 @@ extension NCLogin: ClientCertificateDelegate, UIDocumentPickerDelegate {
             documentProviderMenu.delegate = self
             self.present(documentProviderMenu, animated: true, completion: nil)
         }))
-        present(alertNoCertFound, animated: true)
+        DispatchQueue.main.async {
+            self.present(alertNoCertFound, animated: true)
+        }
     }
 
     func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
@@ -507,7 +511,9 @@ extension NCLogin: ClientCertificateDelegate, UIDocumentPickerDelegate {
         alertEnterPassword.addTextField { textField in
             textField.isSecureTextEntry = true
         }
-        present(alertEnterPassword, animated: true)
+        DispatchQueue.main.async {
+            self.present(alertEnterPassword, animated: true)
+        }
     }
 
     func onIncorrectPassword() {
@@ -515,7 +521,9 @@ extension NCLogin: ClientCertificateDelegate, UIDocumentPickerDelegate {
         NCNetworking.shared.p12Password = nil
         let alertWrongPassword = UIAlertController(title: NSLocalizedString("_client_cert_wrong_password_", comment: ""), message: "", preferredStyle: .alert)
         alertWrongPassword.addAction(UIAlertAction(title: NSLocalizedString("_ok_", comment: ""), style: .default))
-        present(alertWrongPassword, animated: true)
+        DispatchQueue.main.async {
+            self.present(alertWrongPassword, animated: true)
+        }
     }
 
     func poll(loginFlowV2Token: String, loginFlowV2Endpoint: String, loginFlowV2Login: String) {
diff --git a/iOSClient/Networking/NCNetworking.swift b/iOSClient/Networking/NCNetworking.swift
index bcbd2ef709..66021b1aad 100644
--- a/iOSClient/Networking/NCNetworking.swift
+++ b/iOSClient/Networking/NCNetworking.swift
@@ -147,7 +147,7 @@ class NCNetworking: NSObject, NextcloudKitDelegate {
                 completionHandler(URLSession.AuthChallengeDisposition.useCredential, creds)
             } else {
                 self.certificateDelegate?.didAskForClientCertificate()
-                completionHandler(URLSession.AuthChallengeDisposition.performDefaultHandling, nil)
+                completionHandler(URLSession.AuthChallengeDisposition.cancelAuthenticationChallenge, nil)
             }
         } else {
             self.checkTrustedChallenge(session, didReceive: challenge, completionHandler: completionHandler)