Hello @Sahana Gs !
Hope you are having a great day!
Microsoft Certification Program is supported on their own forums. I'd try asking for help with exam scheduling / vouchers in dedicated forums here. (Participate\Ask A Question)
Exams/Exam Registration/General Registration Questions
Exams /Exam Registration and Scheduling/Scheduling with Pearson Vue
Certification Profile - Transcript - Missing Exams or Certificates
Exams / Discounts/Vouchers/Special Offers / Event Offers
Pearson VUE Customer service
Pearson VUE contact / chat
Additionally you can try a different browser to access your certification dashboard.
--Please don't forget to "Upvote" and "Accept as answer" if the reply is helpful --