Hello @Manuela Bedoya ,
Welcome to the Microsoft Q&A platform.
Microsoft Certification Program is supported on their own forums. I'd try asking for help with exam scheduling in dedicated forums here. (Participate\Ask A Question)
Exams/Exam Registration/General Registration Questions
Exams /Exam Registration and Scheduling/Scheduling with Pearson Vue
Pearson VUE Customer service
Pearson VUE contact / chat
Hope this helps. Do let us know if you any further queries.
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