I'm sorry to hear your phone has developed a fault @Me2022
In the Uk according to the Consumer-Rights-Act-2015 it's the seller of the phone that upholds the manufacturers warranty so Tesco should be looking after you.
That said typically Samsung UK would help where possible through a Samsung Experience Store or Samsung Service Centre or in some regions even a doorstep repair service or sending it away.
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.