diff --git a/api/http/handler/stacks/stack_update_git.go b/api/http/handler/stacks/stack_update_git.go
index cfafacbf0..da4df4e42 100644
--- a/api/http/handler/stacks/stack_update_git.go
+++ b/api/http/handler/stacks/stack_update_git.go
@@ -146,6 +146,10 @@ func (handler *Handler) stackUpdateGit(w http.ResponseWriter, r *http.Request) *
 			Username: payload.RepositoryUsername,
 			Password: password,
 		}
+		_, err = handler.GitService.LatestCommitID(stack.GitConfig.URL, stack.GitConfig.ReferenceName, stack.GitConfig.Authentication.Username, stack.GitConfig.Authentication.Password)
+		if err != nil {
+			return &httperror.HandlerError{StatusCode: http.StatusInternalServerError, Message: "Unable to fetch git repository", Err: err}
+		}
 	}
 
 	if payload.AutoUpdate != nil && payload.AutoUpdate.Interval != "" {
diff --git a/api/http/handler/stacks/update_kubernetes_stack.go b/api/http/handler/stacks/update_kubernetes_stack.go
index e5d659a52..9ce74cb6c 100644
--- a/api/http/handler/stacks/update_kubernetes_stack.go
+++ b/api/http/handler/stacks/update_kubernetes_stack.go
@@ -74,6 +74,10 @@ func (handler *Handler) updateKubernetesStack(r *http.Request, stack *portainer.
 				Username: payload.RepositoryUsername,
 				Password: password,
 			}
+			_, err := handler.GitService.LatestCommitID(stack.GitConfig.URL, stack.GitConfig.ReferenceName, stack.GitConfig.Authentication.Username, stack.GitConfig.Authentication.Password)
+			if err != nil {
+				return &httperror.HandlerError{StatusCode: http.StatusInternalServerError, Message: "Unable to fetch git repository", Err: err}
+			}
 		} else {
 			stack.GitConfig.Authentication = nil
 		}
diff --git a/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.controller.js b/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.controller.js
index 1bc7db19e..106446b74 100644
--- a/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.controller.js
+++ b/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.controller.js
@@ -25,21 +25,13 @@ class GitFormComposeAuthFieldsetController {
     if (!auth) {
       this.authValues.username = this.model.RepositoryUsername;
       this.authValues.password = this.model.RepositoryPassword;
-      this.onChange({
-        ...this.model,
-        RepositoryAuthentication: true,
-        RepositoryUsername: '',
-        RepositoryPassword: '',
-      });
-
-      return;
     }
 
     this.onChange({
       ...this.model,
-      RepositoryAuthentication: false,
-      RepositoryUsername: this.authValues.username,
-      RepositoryPassword: this.authValues.password,
+      RepositoryAuthentication: auth,
+      RepositoryUsername: auth ? this.authValues.username : '',
+      RepositoryPassword: auth ? this.authValues.password : '',
     });
   }
 
diff --git a/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.html b/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.html
index da5761f04..bc6f762a4 100644
--- a/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.html
+++ b/app/portainer/components/forms/git-form/git-form-auth-fieldset/git-form-auth-fieldset.html
@@ -41,7 +41,7 @@
         class="form-control"
         ng-model="$ctrl.model.RepositoryPassword"
         name="repository_password"
-        placeholder="personal access token"
+        placeholder="*******"
         ng-change="$ctrl.onChangePassword($ctrl.model.RepositoryPassword)"
         ng-required="!$ctrl.isEdit"
         data-cy="component-gitPasswordInput"
diff --git a/app/portainer/components/forms/stack-redeploy-git-form/stack-redeploy-git-form.html b/app/portainer/components/forms/stack-redeploy-git-form/stack-redeploy-git-form.html
index bb9c6585e..f7fe3789a 100644
--- a/app/portainer/components/forms/stack-redeploy-git-form/stack-redeploy-git-form.html
+++ b/app/portainer/components/forms/stack-redeploy-git-form/stack-redeploy-git-form.html
@@ -38,7 +38,7 @@
     class="btn btn-sm btn-primary"
     ng-click="$ctrl.submit()"
     ng-if="!$ctrl.formValues.AutoUpdate.RepositoryAutomaticUpdates"
-    ng-disabled="$ctrl.isSubmitButtonDisabled() || $ctrl.state.hasUnsavedChanges || !$ctrl.redeployGitForm.$valid"
+    ng-disabled="$ctrl.isSubmitButtonDisabled() || $ctrl.state.hasUnsavedChanges || !$ctrl.redeployGitForm.$valid || ($ctrl.formValues.RepositoryAuthentication && !$ctrl.formValues.RepositoryPassword)"
     style="margin-top: 7px; margin-left: 0;"
     button-spinner="$ctrl.state.redeployInProgress"
     analytics-on