Hi!
I would contact MS through the chat you have access to through your MCP-page to get an answer, but I don't THINK you have the right for a second shot if you missed the appointment the first time.
https://www.microsoft.com/en-us/learning/dashboard.aspx
Best regards
Andreas Molin
Andreas Molin | Site: www.guidestomicrosoft.com | Twitter: andreas_molin