If I have
Microsoft Office Specialist: Microsoft Office 2016
what i should do to have
Microsoft Office Specialist: Expert (Office 365 and Office 2019)
Microsoft Certification is currently not supported in the Q&A forums, the supported products are listed over here https://docs.microsoft.com/en-us/answers/products (more to be added later on).
You can ask the experts in the dedicated Microsoft Certification - Exams forum over here:
(Please don't forget to accept helpful replies as answer)
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