Loss internet connexion with AP1301

Hello, I need help for the installation I made for my client. This one is composed of 5 AP1301. When everything works, I reach speeds of 300mbit/s (I specify that the customer has fiber optics and I speak here of the internet speed), then the speed decreases to around 25mbit/s, response time of the AP longer and longer, then no more access to the internet, without losing the wifi link, and this all day long several times an hour. Knowing that during this time when I lose internet with the AP1301, another computer is directly in ethernet and internet is working perfectly. Is there something in the configuration of the AP that could cause this problem? Have you ever encountered this problem? Thank you very much.

Hello here again

Same answer, which Stellar release installed? Thank you in advance

Hello here again

Same answer, which Stellar release installed? Thank you in advance