WAC505 Wifi Connection Problems with Mobile Devices

Hi,

For some time now, I have set up multiple WAC505 Accesspoints throughout my home. For all Computer end devices the connection works flawlessly. For mobile android and ios devices however, a wifi connection with internet access is established for a short while  before being kicked out. After reconnecting the same problem returns.

I have already checked that the firmware of the AP is up to date, but with no luck.

I would appreciate any help.

Thanks