Telegram is full of scammers and impersonators as well as spammers. It is hard to get important information in crowded telegram chat group except checking their pinned messages.
Wolbet's official representative didn't log in or make any post here for more than a year. But some members like Zwei and others are doing good job by notifying us about the major updates.
You can also follow them on Twitter from
here. They are very active there and run some cool contests and giveaways from time to time. It's safer than telegram, imo.