Unfortunately when a phone is imported from a country to use in another country then some features may not work correctly @MatusJ or work at all.
This happened to me when I imported a Samsung Note 20 Ultra from Samsung Hong Kong.
Samsung Pay didn't work and the Benefits in the Samsung Members App were blank and most content was for the country it was released to be used in.
It's to do with the software and csc code.
Also Samsung UK won't offer support to an imported model so there's no 2 year manufacturers warranty.
In regards to your phone all you can do is check in every relevant setting and preferences settings that UK / English is chosen.
I wish you all the best.
Daily Driver > Samsung Galaxy s²² Ultra 256Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I have no affiliation with Samsung.