It’s a long shot, but there has been a plethora of people complaining that launchers keep asking to be set as default, the problem being attributed to the ‘Well being’ app. Maybe something similar is happening here
Have you tried a) A Safe mode start and b) disabling the Well being app and as many others of the default you can?
https://support.fairphone.com/hc/en-us/articles/360048843571