This is only for the user who is instructed to do work that he doesn’t have access to. Your solution is hidden between security only.
Might be , that you could have forgotten to give access to data source microflow to the current user
you could have missed “allow creating deleting” object in access rules
Hope this helps!
Usualy this is because the user that is executing the action is not allowed to see or change a certain entity, attribute or association.
Most of the time in the log there should be a little more indicators as to what entity this specifically applies.
Then you could check if the user indeed has the specific acces.
An other option is that you are trying to change the Account or User entity. In that case also have a look that the user that you are doing the changes with can manage that specific user role: https://docs.mendix.com/refguide/user-roles/#user-management