@Kostispan I am happy for the solution with my advice, but do not forget that if you have a power cut in your house, or you touch the network optimization in the deco application, you can change the...

@Kostispan Restart the main deco as many times as necessary, until you get a channel on the 2.4 Ghz frequency that is between channels 1 and 11. then deco m5 will detect its fan.

@Kostispan If the fan is American, the wifi module in the 2.4Ghz frequency only works for channels 1 to 11. Your deco m5 may be that in the 2.4Ghz frequency it is tuned to channel 12-13 or 14, in...

@YCNg Could you please briefly describe how the option is implemented in the beta firmware. You cannot select which deco connects with the one chosen by the user. I have 5 decos (I just added one)...

@ -OJ If you can connect without problem. I have it in two of my decos m5 slaves.

@gammy999 I get him to change the channel number in 2.4Ghz. RESTARTING the MAIN DECO on the tp link application website. I repeat only restart the main one, if necessary repeat the operation again.