Hello @Phong Dinh
Welcome to Microsoft Q&A Platform,
Microsoft Certification Program is supported on their own forums, in this case I'd suggest asking for help by contacting Pearson VUE Support directly:
Pearson VUE - Customer Service: https://home.pearsonvue.com/Test-takers/Customer-service.aspx
Pearson VUE - Chat: https://home.pearsonvue.com/microsoft/contact
As alternative you could raise a question in the Microsoft Certification forums:
Microsoft Certification - Exams: https://trainingsupport.microsoft.com/en-us/mcp/forum/mcp_exams
Microsoft Certification - Exam Registration: https://trainingsupport.microsoft.com/en-us/mcp/forum/mcp_exams-mcp_exam
I hope this helps!
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