Strange behaviour by Teams - update loop

It started a week or so ago - when a user wants to join a Teams meeting, Teams open and the below alert is shown (update by Tuesday, March 9th 2021).

In a second or two Teams close, and this is shown:

Then I click on the link, download and install Teams, Teams start again and the loop repeats.

I tried deleting Teams cache, but it didn't help.

I uninstalled all instances of Teams (teams-wide installer, etc), but it didn't help. 

Windows 10 are updated.

Any advice will be much appreciated.