I just came back. I had a z fold 3 and it died on me. I had zero problems with it and just randomly about 2 weeks ago, it got suuuper hot while charging and self destruction. I'm soo glad I kept my good old Note 20 Ultra. I love this phone soo much. But I do eventually want to get back to my folds. They are just soo much fun to use.
I think that's a relatively common issue in the US. You can flash an update with a PC, and I think I remember hearing that if you put a SIM from the old network in the phone will update. Not 100% on that, but it's worhth a go.
FAQ for Samsung MOBILE. Find more about 'Where can I download Samsung Smart Switch for PC?' with Samsung Support.
Connect your phone to your PC with an USB cable & run Smart Switch from the PC. It should detect if there's an available update & it can download & install it from the PC to your phone. If not, you may need to flash the software as @fuzzylumpkin mentioned.
You might also try to clear your phones Cache Partition. It's definitely worth a try!