Problem with group mail accounts

(suitecrm V. 7.11.18)

I have set up 2 incoming group mail accounts. If I log in as administrator I can see both of them and switch between them by clicking on the button
If I log in as a user I can see only the last account.
If I click on the button to change the inbox/account I get the following screen.
In other words, users are not able to switch between mail accounts
What is the problem?

Hey! Check this short guide out on the last post of this thread.