New upgraded phone overheating and constantly in for repairs

I upgraded at Chatz The Park Pretoria this year.

I upgraded to Samsung S21 Ultra.

After 2 weeks of having the phone I could feel that the screen and camera gets extremely hot.

So hot that when I want to take a picture it says 'temperature too high'. The battery also does not last longer than 14:00 when it was fully charged the night before.

I took the phone back to Chatz The Park Pretoria, only for them to send the phone for repairs FOUR TIMES. Every time I have to wait 7-14 working days to get my phone back.

They apparently cannot find anything wrong with it.

This is a brand new phone that I have not been able to use for more than 2 consecutive weeks.

I took the phone to Chatz The Park PTA and the sales person also felt how hot the phone was and confirmed that the phone was clearly overheating.

What do I do now? Cancel my debit order? Cancel my upgraded contract?

I will not settle for this phone giving me consecutive problems within the first 2 weeks of using it.

I am highly upset and I demand an answer and a new phone.

I will not pay a rand more for this brand new phone because I cannot use it (it is always in for repairs, has a flat battery or is overheating).