Welkom battery centre poor service

I have a 2013 be T5 75KW vehicle A year or so ago I went to battery centre to check what the issue is with my car and they informed me the battery was too small so I said well put the right one in which they apparently did now come 2020 and 2021 I had no issues for a while but with the cold weather my car won't start and I went for a test and low and behold I'm told this battery is the wrong size for my car

Absolutely pathetic and the warranty at the time could not be carried out I have to buy a new battery