Mate that's the nuclear option I might have to reserve when no one is in the house. I remember I had done this to figure out why my 5G was sketchy and it finally settled.
Currently very unlikely I can do this for various reasons. Everyone in the house needs stable internet, school, Uni, Work from home etc. Cant stuff it up........ now. Maybe my final option.
You are definitely on to something.
Apr 16 14:23:27 HTTPD: [LOGIN][https][APP] failed (91.199.163.54)
also this IP 78.128.114.42
Unsure if these are from the Asus app though. The App has the same problem logging in fine when the UI works. So does it not mean it logs in fine and may not be the issue, instead these above IP are attacking? Sorry if I seem clueless.
As per your suggestion I have turned the "Enable Web Access from WAN" is set to "No".
Fingers Crossed.