WLED disconnecting from wifi randomly

So here’s the story, i have 3 gledpto controller with ESP8266, i’ve always had issue with paring them to the wifi, but i found a little trick just by restarting the router they were able to connect and keep the connection.

I’ve already separated the 2 wifi frequency, i gave to the 2.4 ghz a fixed channel to n. 6 which was the less populated, i’ve already gave to the wled controller a fix IP from the router, i’ve also tried some other ESP8266 and same story.

Now the problem is that I’m getting out of my mind because they drop off once every 2/3 days and they are not reliable at ALL.
Also, if i change the lights too fast, they disconnect and reboot, and sometimes i need to restart the router to let them join again.

The signal strenght is, good.

What can I do? I was thinking that MAAAYBE the router is shitty? Idk guys let me know if you have some suggestions…

Oh and also, i’m not able to connect to them, in the wifi settings i see them connected!

I am not really sure that is the same case as you have but you might want to look at this post