Tor not working with VPN on host with Whonix KVM

I’m having the trouble connecting to tor with a VPN on host. (the connection has timed out)
I need the VPN on host due to the fact that I will be living on a place with share wi-fi over the next few months.
How can I use a VPN on host and connect to tor inside my Whonix KVM?

reddit post with the exact same issue, as it seems its a mullvad / whonix KVM problem. Anyone got a way to fix it?

Set your MTU to the highest possible in the Mullvad App if you are using WIreguard.