NFC not working until iPhone fully restored

Hi

I have a very strange problem. At some point my Apple Pay stopped recognising terminals in stores, like NFC wasn't working. I brought it to the services point, they checked with their NFC device, and it wasn't working neither. They took it restored it and NFC started working again. I logged in to my Apple ID (I didn't restore the backup, I set it up as a new device) and added my cards – Apple Pay started working again. After 5 days it stopped. In service point they told me that they can't repair it because it seems that NFC is working. But I keep restoring phone, Apple Pay works perfectly for a while and then again it stops. I can't restore and set up my phone as a new device every week...

When it comes to online payments Apple Pay works perfectly at all times.

Does anyone have any idea why it can be like that and what can I do to repair it?

Thanks!

Kacper