Ever since the 1999 update I've not been able to host any lobby as every invitation fails, what gives?

I've tried to host multiple lobbies many times but every invitation I get to send fails and mostly it sends the "host unreachable" error.

This is weird however, because as soon as I get any one person in my lobby or join another lobby, every invite I send never fails.

This is specially awful when trading or doing any sort of relic shares as I either find someone already hosting or I need to hope they can host after telling me to invite them.

Is there any solution to this?