Ok, I got it. Stupid mistake...
I've been so busy that my phone has never been on charge long enough to get above 90%... so the battery saver feature was on.
Weird thing is that I checked the battery saver function, as I knew that would disable NFC, and it was not enabled.
But this morning when I unplugged my phone, there was a notification saying Battery Saver has been disabled, something something your device features are enabled.
And when I checked NFC by trying to read a tag, it was working.
Seems a bit counter-intuitive that you can enable and disable NFC without any indication that it's not going to work because Battery Saver is enabled.
Thanks everyone