Faulty iPhone warranty with Argos or claim consumer law

Hi anyone working in Argos

When buy a iPhone is the first 12 months with Argos or Apple if device goes faulty

And after 12 months who do we claim consumer law warranty and how long is that for

iPhone battery health on iPhone 11 has gone low pretty fast & phone freezing since few weeks in buying,

Restarting phone did help it but would like to know the above warranty and rights please as seen posts Argos are terrible with solutions