Nginx 403 forbidden

Hello, could you help me to solve this issue?

So i've hosted my API on melztam.serv00.net but suddenly few hours ago it stopped working when accessed from the android device.

Is it possible the WAF causes this?
I've disabled it (previously was set to level 1) but it's still saying forbidden 403.

Thank you in advance

melztam disable WAF and check if problem still occurs.

i can confirm that the API is accessible from browser, but when using the android app i got 403 forbidden