Souup

As someone who just spent today ripping my hair out with the same issue, hopefully this can help someone. As I also had a solid setup for a year until recently. I'm purely a hobbyist so please feel free to correct me. After resetting credentials on the protonvpn side and updating the docker settings, also download a new configuration file and make sure that is reflected in wg0.conf in your wireguard folder. At time of posting my wireguard configuration on Proton is set to expire in exactly a year, hence the "rock solid setup for a year now". Credentials probably just expired, wireguard wouldn't connect and it resulted in dns issues. Just my take, hopefully it helps.