I just picked up an iPhone 12. I upgraded from an XS. I bought a Choetech QI wireless charger back in 2018 that worked great with my XS. It does not work on the 12. When I put the phone on the mat it will make the noise like it is charging and will show for a few seconds that it is charging, but the mat starts blinking meaning it isn't charging.
I hope they fix this soon as I really don't want to have to buy another wireless charger and I don't want to go back to having to plug it in every night (first world problems lol).
Edited to add I updated to 14.3 before I set up my phone and I have no case. It still doesn't work.