The Nomads.com chat is actively moderated to keep it a nice place. Sometimes users are timed out for a few minutes to hours if they break the rules.

The most common reasons for being timed out are:
1) trying to post self-promotion links/spam
2) trying to DM spam lots of people when you just signed up
3) not following the guidelines
4) being not nice and fighting with people

There's a reason other digital nomad communities are predominantly 90% self-promotion spam and self promotion and Nomads.com isn't. But that requires moderation, which is a choice.

If you don't like to follow the rules, find another community to participate in.