Issue with RB-911G-5PHnD

I have an issue with RB-911G-5HPnD with 3 Connected customers

Two of the clients keep connect and disconnect repeatedly.
I tried to change the frequency and choose a non usable channel, the log shows “disconnected, extensive data loss”.

I tried nstream with polling and without polling and tried nv2 protocol

Any suggestions ? " I am an amateur with MikroTik "
Please, Can any one help me ?

Seems you’re having interference problems, so the first to be ironed out is wireless.

Start by issuing a spectral scan to see which channels are optimal at the AP, open a New Terminal on it and issue:

/interface wireless spectral-history range=5Ghz wlan1

Leave it running for some minutes and post an screenshot.

Check the attachments for the results

Note :- noise floor is -124dBm " Could it be interference ? "
Sector.PNG

Any one can help ?

Try using the 5900 frequency, note the spectral history black area, that means is “empty”. Does it get better afterwards?

Thanks for your help
problem solved
it was an interference problem at the customer side not at AP side