I'm unable to pair iPhone 15 Pro Max Apple Watch Series 9

I’m trying to pair my iPhone 15 max Pro with my series 9 Apple Watch but on the app it’s not popping up but when I get a call or when I get phone calls ring on my phone on my wrist or sometimes I get hand there but I haven’t use my watch for a while and I’m trying to pair it to my phone and it’s not popping up on the application on my phone But at the store, they paired it and connected it can somebody help me out on this situation?

[Re-Titled by Moderator]