Hi Vicky,
Thank you for contacting the Microsoft Community.
I appreciate your time and effort to complete the Microsoft Virtual Training Event. I know the importance of completing the event to enhance your knowledge and skills. Allow me to extend my assistance to have this resolved.
Since you encountered an issue before the event, we kindly request you to re-register on another training course to get a new invitation to join the training course. For your reference, you may visit Microsoft Events Catalog for the upcoming online sessions. This only happens intermittently, and it won't be an issue after you re-register.
In addition, you may also access Microsoft Virtual Training Days Discounted Certification Exam FAQ page and feel free to check out the sticky post for additional reference and guidelines about the Microsoft Virtual Training Day Event.
Please let me know if you need further assistance, I'm more than happy to help.
I look forward to your response. Please note that if no response is received after two business days, the case will be closed and locked. After the case is locked, we will no longer be able to respond. Thank You.
Sincerely,