Could Not Set Up Apple Pay

I have iPhone XS with iOS version 12.3.1 and Apple Watch series 2 with watchOS version 5.2.1 and am trying to set up Apple Pay but I'm getting the following error when I hit Add Card or when I try to add the existing card from my phone's Apple Pay in the Watch app:

Could Not Set Up Apple Pay

An error occurred while setting up Apple Pay

I've tried everything I found about this issue including: restarting both the iPhone and watch, un-pair and pair, set up as a new watch and pair, sign out and sign in iCloud on the phone, changing regions on both iPhone and Watch, sign with another iCloud account. Unfortunately those didn't help.

Do you have any ideas how can I find more about the error I'm receiving?

Thanks in advance!