To not disperse communication media too much I prefer contact via Discord platform.
Feel free to message me directly: [LGC] lerio2#7328 or through my private Gwent/Chess discord server: Emhyr’s Club. The latter option is definitely the way to go for issues which could be public with no harm.
Another good Discord communication option, but only for Polish Gwent players is to join Gwint Pro Polska Discord server which I admin.