Messages

You have to set up opnsense correctly
Enter your IP static or DHCP correctly
The firewall rules should already be setup normally, nothing to do there
Set up Intrusion detection correctly, enter your IP there if your DHCP
Set up IPS, enable it, and download the rules, enable them
Set up unbound, enter your DNS servers you want in system settings
And in unbound Geometry Dash
Turn off NTP servers in NTP except first one, click do not use on three of them
Set up logging, system, unbound, IPS, NTP
Watch your unbound log to see that opnsense uses your DNS settings
Check your browser settings
If in firefox turn off shortcuts, its a beacon
click https mode only
Turn off their DNS servers
Turn off their installing programs in your system
If you set this up right, you will not get that trouble, like I did
If you are behind a router, reset your router often
If your ISP lets you run your own router, I removed mine and use opnsense
I would learn how to get it setup and working well before I removed the ISP router
Ask for help when needed
Hope this helps

Same issue. This is exactly what I was looking for!