iPhone 13 random issues

I bought my iPhone 13 at an t mobile store on January 7, 2024 and I’ve had lots of problems with interruptions and not getting the appropriate app I need, it gives me a complete different view, also it turns on off and on and goes haywire. I so tired of addressing my problems to the T-Mobile and iPhone. I have been a the help area with apple and they will not exchange my phone. It is still under warranty. My name is Melba.

[Edited by Moderator]