I have my module installed on a portal. On the child portal, I create an instance of that module. I login to the child portal with a user id that does not exist on the parent portal. I can operate the module, but when I hit one of the submit buttons on the module, I am taken to the login screen of the child portal. I tried to step through my code, but found that the redirect is done at the DNN level, not the module level, because of Request.IsAuthenticated being false. Please note that I do not see this behaviour when I am logged in with a user id that exists both on the parent as well as child portal.
I am not sure why this is happening. What can I do to avoid this behaviour?
Thanks in advance.

Thanks Scott!
I checked the Event Log, there are no errors recorded there.
Regarding page permissions, since the user is able to operate the module, it has permissions to view the page, right? The problem is only when a submit button is hit on the module. I hope I understood your question correctly.

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