Deco x60 radar issue

Hello, I have a set of Deco x60 that has worked wonderfully for about six months. The main one is connected via a modem in bridge mode; the other is connected via Ethernet to the first. About 25 devices are connected to the network.

However, for a couple of weeks, I have had internet connection issues on my 5 GHz Android cell phones and Windows laptop. All devices experience issues simultaneously and randomly. One phone may work perfectly while another has internet dropping every 2 minutes (randomly).

At first, I thought it was related to my new home assistant installation, which includes about seven Zigbee devices. Because they operate on 2.4 GHz, I ensured they were on a different channel (25 vs. 6).

Then I noticed that when having issues, I would receive a notification on the Deco app mentioning it automatically switched from 160 MHz to 80 MHz because of radar detection. Something I had never seen before. So, because it's related to 5 GHz, I thought I had found the issue. So I reset the Deco, setting it to 80 MHz. It worked for two days, but the issue reappeared.

Each time I reset the whole network, it works fine for a day or two. I never had any issues with the same setup for the first six months.

I tried different settings on the problematic phones: fast roaming, static MAC address, beamforming, static IP, etc., but nothing works. I am about to buy something else. Can someone help?

Thanks