Ok I have already see this issue, there is a problem in channel, I can be wrong but for me it’s from the one memorised on the conbee and the one in the config.
You realy need to have the same in phoscon and deconz.
Follow exaclty the mimic procedure
Click “Leave network” in deCONZ
Open network settings and change the channel and click “save” them “done”
click “join network” again.
You can too relaod the old config, if this one was not currupted Network lost issues · dresden-elektronik/deconz-rest-plugin Wiki · GitHub
Else I don’t know the correct procedure, perhaps changing the channel in phoscon instead of phoscon.