Hey there @Tristan50221 - great question! Thanks so much for posting, and I hope you’re having a good day so far! 

I’ve seen this issue many times with Calendly users - and it’s usually a pretty simple fix! 

The very first things I’ll suggest might seem too simple and a little silly - but! - are often the fix: 

• double-check that you are (external to Calendly) logged into the same MS Teams account that you have integrated with Calendly when you attempt to join these meetings - otherwise, you will not be recognized as the host
• double-check that you (internal, within Calendly) integrated the correct MS Teams account on your integrations page or via your connected calendar on your Calendar Connection page (especially those users that have MS Teams automatically connected via their connected calendar often find that the MS Teams account they are using is not the one they thought they were using, since that integrations comes automatically with the calendar connection) 
• double-check that you are joining the meeting from the correct link
• double-check that you are connected to the internet
• troubleshoot your WiFi/network settings
• clear your cache/cookies (steps below) before trying to join via meeting link again

How to clear browser cache

If this does not resolve your issue, please let us know and send any further screenshots or details that might help us troubleshoot!

Here is some more information that might also prove helpful: 

• a topic from Microsoft Teams Community where users had the same issue and answers from support
• another topic from MS Teams Community - the same
• Microsoft says to double-check that your MS Teams and Outlook accounts are logged into the same accounts (email addresses)