Scenario: There is an custom SharePoint app/Add In which has got 4 different types of groups for 4 different types of users. 4 different groups have permissions are Full Control, Contribute, Contribute and Read respectively.
The app is being run in SharePoint On-Premise.
The app is having Managed Permissions. The problem is the users which are present in the groups having Full Control are able to login to the app but the ones below Full Control like Contribute and Read are unable to. For users below Full Control, the app is asking to login again and again.
However, when the app is run on SharePoint O365, there is no such issue.
Can anyone tell me what is the reason behind it? What is causing this problem? Even the guesses are fine for me.