Telegram is not blocked yet. Try growing your own telegram channel or a group.
Fill it with the unique content, invite all the members of your team and your contact list to get the first 100 followers.
Place the link to your channel on different forums, Quora, Reddit, etc.

After your cross 500 users mark, try paid advertising on other channels.

You can find more tips in my article:
medium.com/@kate.poisonglen/17-tips-to-launch-the-telegram-channel-for-a-crypto-project-f262cd041c81