Also, it asks me the password from time to time on both 2.4 and 5Ghz SSIDS, even when I haven't changed it at all. I entered the actual one, and it rejects it! It's crazy. Then it appears and connects itself.
I had something similar with one of my RPi (the only one without cable), became it far better after switching off the "zeroconf" (settings/services/general) and applied an auto reboot cron job for every night. Try it too if you want.
But that is true, something could be wrong with the wifi connection in LE ("iwd[393]: event: connect-failed, status: 16"), I have devices using the same wifi (phones, tablet, laptop), none of them had any same (re)connection issue (waiting for the password, but doesn't accept).
I keep my previous opinion, if you have any possibility to switch to cable, do it! Far better connection, no more password-encryption, stable speed...