I have the same issue and no one has been able to give a answer. Most of the solutions they give me is to reset them but you can’t ssh in or telnet in
Once you reset them, they have a default IP and default credentials on the back. Connect to them hardwire using a system with a system configured on the AP's default subnet. Log into it using the https web interface (port 443, I believe) and you can configure them from there.