Garmin Pay isn't working anymore, after a software update (I'm pretty sure of that)

I've had my Venu Sq for less than 6 months. I used to be able to use Garmin Pay to pay for my groceries. Somewhere last week, it stopped working. In my supermarket, it's fairly common to pay with NFC. I tried: deleting the card in Connect and adding it back, restarting my phone, restarting my watch, deleting the cache files of the Connect app, resetting default settings on the watch (and adding the card again), and nothing seemed to work. The terminal says: "Kaart geweigerd. Lees chip, magneetstrip of andere kaart", which basically says: "Card declined. Read chip, magnetstripe or other card". Our bank cards are Maestro cards here, in the Netherlands, and I've added my bank card as Maestro. I have contacted my bank, they saw my card is successfully connected to Garmin Pay, and said it might be my NFC chip being damaged. Great for them to blame it on my NFC chip, but I've been so careful with my watch, that it can't be damaged, that's pretty much impossible. 

After I had that software update on my watch last week, this issue started. 

I'm not looking forward to have to send my watch back to the store I bought it from, to get a new one, because I'm careful with my watch. I went on Reddit and another Dutch person also has this issue with her Venu Sq. She got it in January, and has never been able to use it. She's with a different bank.