The latest update which changed One UI from 6.0 to 6.1 didn't correct my phone's inability to connect to WiFi networks. Samsung said to get another phone. It's only been paid off for year. No way!
The update wasn't meant to fix specific problems. If I recall, the S21 had a problem with the antennas, so no update will fix a hardware issue. You can either see if it can be repaired by having the antenna replaced or you can upgrade your phone.
I took it in to get repaired. The repair person told me it's not a hardware issue, it's software. I've checked with other professionals as well, same thing.
The S21s were problematic with the wi-fi after the 6.0 update and 6.1 did nothing to fix that particular problem. If you haven't already, reset your network connections and see if that helps. If it does not, make sure you have a current backup of your device and a separate backup of any important data and photos and then factory reset your phone and restore your backup. If that does not help, your only 2 alternatives would be to put in an error report with Samsung and include your phone log, or follow the recommendation to get a new phone. I recall that after the 6.0 update there were many people on here with S21s complaining about that very issue. After the 6.1 update, I have not really seen very many repeat complaints on it. I don't know if that means the issue was resolved for those people, or if they just gave up. The fact is the phone is nearing the end of it's update cycle and life cycle, so upgrading might be the better course of action.
