NFC not working after flash/akku replacement.

Hey, I hope someone else here has an idea, as I no longer have any solutions.

Tldr:
Backglass replaced - flash broken - nfc working
flash and akku replaced - nfc not working
charging coil replaced - nfc still not working

What happened and what did I do?

I dropped my Iphone Pro 13 and the glass back broke. I replaced the back and broke the flash in the process. The phone worked perfectly at the time, just not the flash.

1. so I ordered a flash and if you have the phone open anyway, I also ordered a battery at the same time.

2. then I replaced the battery and the flash. Everything works perfectly except that now no NFC things like Apple Pay etc. work.

3. after long research I found 2 problem areas. The NFC antenna is in the charging coil. And the “antenna” is also part of the flash. Both components were involved in my repair.

4. charging coil bought new and inserted. Everything works except NFC.

Now I'm stumped and don't know what to do. I have not noticed any damage. Adjusting the flash module several times has not helped either. Should I buy a new flash module and try again? Or am I missing something else?

Many thanks for any helpful answers.