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Hello @KOKKILIGADDA SIVA SANKAR
If the payment was successful and the date was scheduled, your friend should have received the email for the same.
Check your Learn profile for an exam appointment on https://learn.microsoft.com/users/me/credentials/?tab=credentials-tab
If you are still unable to find it there, next step will be to contact support via https://aka.ms/CertificationSupport.
You can additionally reach out to OnVue support: Pearson VUE - Customer Service
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