You posted on the wrong section. You posted in the Romanian side of the platform.
If it was done by mistake, maybe you should post in the UK forum.
If you are Romanian, try posting in Romanian please, this way you will receive answers from people facing the same issue as you.
No worries, welcome on the platform!
Maybe somebody will be able to assist you. Unfortunately, I don't have a tablet and I don't use an SD card myself ( I am guessing it would be the same on a phone).
Are you referring to the One UI 3.0 update? You mentioned 3.1 but I don't think it is yet available for other devices except for the S21 series.
What do you use to browse the folders? Are you using the Files app?
Try downloading a different app like Total Commander from the Google Play store and see if you can access all the folders on the card.
Ah, awesome. I didn't know you got the 3.1 on the S7 already.
Give Total Commander a go, just to see. It is weird that you don't have access to a browsing app (maybe you have permissions that need enabling for the app).