Same problem here, I had google pay before on my Samsung Galaxy Watch together with Samsung S10+, which worked. Now I bought myself a Samsung Galaxy S23 and had to reconfigure stuff, reset watch and reconnect. Bunq and Google Wallet on my phone works, but adding to my watch keeps saying that I should "Call my bank", in dutch.

I tried everything on this forum. Resetting, clearing cache, rebooting, automaticly adding, manually, but the result is the same.