I’m not sure if it’s the same problem but you will find a long thread about MobilePay/Vipps problems here: MobilePay stopped working, again - #53 by Bettina
As far as we could deduce, it’s because the banks / VIPPS use Google Play Integrity API to check if our phones are “safe” for the bank to admit. Which is a very weird way of doing it, of course, with all kinds of problems in itself. Which is why I wrote to the Norwegian Finanstilsynet and complained (they never wrote back) Link to the letter is further up in the thread I linked to.
However, what has worked for me has been to go to the apps overview in settings and choose Mobilepay/VIPPS, then storage & cache. And then delete storage. This means that the app is setup again, so I need to key in my phone number, reidentify and choose my password again. Then it works - for a while.
However, it has actually worked for a month now, which is the longest yet. Don’t know whether Murena did something to facilitate this? But before, I was typically logged out within 24 hours, so if it lasts, it’s a big improvement!
I also add the link where I keep a documented list of my complaints to authorities about this, because I will not go down without some fight <3 #DanmarkSkifter - guide til at finde din motivation - integral-lifestyle.dk (see the bottom, most of it is in Danish, but let me now and I can translate to English).