VPN2S router very slow webui or stuck on login

Hello, I have a VPN2S router and 2 NWA1123 access point.
Everithing appears to work well except the login on webui of the router, which is so slow and mayor of cases goes on timeout.
Some times works, other I have to refresh the browser a few times, some times appears to be impossible.
There are times I'm in and then it goes out on the login page.

Please help


#Biz_Feb_2020