Authentication prompt repeately popup Outlook for Mac 16.67 (22101000)

Hello,

I'm running Outlook for Mac 16.67 (22101000) and I keep getting the authentication window for my MS 365 all the time.

One account using Okta authentication has the authentication popup every 2 minutes, this one closes automatically.

Another account, which uses external authentication, is unable to log in at all.

Any idea/help on this one?