Internet drops in Firewalla blue plus

Hi Just got the firewalla Blue Plus (three days now) and my setup is an Airport Extreme connected to the Service Provider Modem-Router. The Firewalla is connected to one of the ports of the Airport Extreme.

After having internet drop all night yesterday, I decided to reset it to factory hoping it would stop dropping but it still drops the internet. 

What I have learned is that when the Airport Extreme stops working (no internet reaching the devices), I disable and enable the wifi from any device (computer or phone) and the Airport Extreme provides internet to all the devices again. very weird...

Any conclusion or advice? 

Thank you!