Are you logged in with the same email address?
Make sure you are logged in to your Buzzy account with the same email address as you were invited to the Buzz with. For instance, if you receive an invitation to join a Buzz at one email address (eg me@my-personal-email-address), but sign in to Buzzy with a different email address (eg me@my-work-email-adress), Buzzy won’t know that you are the same person that was invited to the Buzz.
Has the Buzz been published?
If you have been invited to the Buzz as an Audience member (ie not with edit rights), you will only see the Buzz when it is Published. If the owner puts the Buzz back into ‘Draft’ status again, you won’t be able to access it until they Publish it again.
Has the Buzz been deleted?
When someone deletes a Buzz, it is deleted for all its participants.