Hi,
A support moderator in Microsoft Credentials forum can help get your certificate to show up and merge accounts. To contact them, please ask your question using link below. They will respond to your question within 2 business days typically:
https://trainingsupport.microsoft.com/en-us/newthread?threadtype=Questions&forum=mcp
Please click Accept Answer and upvote if above was helpful.
Thanks.
-TP