Dual sim card setup not working with AdAway

[guzzard]

I run LineageOS 15.1 on a Samsung Galaxy S9 with dual sim. Only one of the sim slots seem to use the host file? When running data through the other sim card it seem to bypass the hostfile and any host can be reached.

I tried switching sim cards physically to see if it made any difference, but it seems to be connected to the actual sim card, not which slot the sim card is in.

What might be going on here? Wifi is also blocked correctly by the way.

[Vankog]

Interesting tidbit.
What's the provider?

Could have a lot of reasons.
Maybe a kind of VPN by that company or a particular DNS config...