Hi Florian,
Thank you for contacting the Microsoft Community.
I understand how important it is for you to ensure that you've successfully registered for the PL-300 exam. Rest assured, let's work together to promptly resolve this issue.
To locate and verify your account, please provide the necessary information that I initiated through a private message.
For immediate assistance, please contact the Pearson VUE support. They have the necessary tools and access to reschedule your PL-300 exam and find options for you. Pearson VUE offers live phone support for real-time assistance, and you can select your region to view all available support options. Additionally, they have introduced a live chat feature that allows you to speak directly with an agent.
Pearson VUE Support: https://www.pearsonvue.com/us/en/microsoft.html#contact (kindly share the Case ID through the Private Message if you have already contacted them and need further assistance from us.)
Moreover, if you are an active ESI learner (part of an organization that is affiliated with the Enterprise Skills Initiative), please contact the ESI Support Team, kindly refer to our private message for their contact details.
If you need further assistance after contacting ESI by us monitoring the case, please send me the case ID they provided. This will help me decide the next steps to take.
Meanwhile, since your unable to locate the email confirmation, please consider checking your email inboxes, including your spam and junk folders, for any confirmation messages from Pearson VUE or the exam provider.
Additionally, for your exam rescheduling, please note that you must cancel your currently scheduled exam before booking a new one. This cancellation must be completed at least 24 hours prior to your scheduled appointment; otherwise, the fee will become non-refundable, and you will be marked as a 'No Show' for the exam. You may refer to Reschedule and cancellation policies | Microsoft Learn for your reference.
I look forward to your response. Please note that if no response is received after two business days, the case will be closed and locked. After the case is locked, we will no longer be able to respond, even through private message. Thank you.
Kind regards,