You right ! I reboot the router and it looks good and I don't have the error in the log system.return or RMA!
My first 86U had the issue that it doesnt apply Wifi changes, only after a reboot it changed it to what I set before.
Later I found just disable 5G in prof-tab and reenable again made changes too to be really applied and not only shown in GUI.
The trouble comes from the 5ghz settings and uncheck the DFS option and hit apply and reboot resolve the problem
Thanks guys for your advices it really helped me !
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