And why are you using Google by the way to contact them? It's very dangerous practice for crypto enthusiast as you might fall for scammers trying to copy exchanges or whatever services related to crypto with this kind of approach. So stay away from, and be self-aware of security hygiene here.
It's one of the ways to contact them, so why not.
To OP just because the email had an error and bounce back does not mean you need to distrust the service, try to find other ways to contact them. There are lots of the ways including what had mentions above, you can even try to contact them via their social media accounts.