Hello Mahesh,
Thank you for contacting the Microsoft community.
I appreciate your dedication for Microsoft Credentials as I understand that you are having an issue with registering for your exam due to an error message that you have reached the maximum number of exams scheduled. Allow me to assist you with your concern.
For us to provide further options and recommendations, please share the information requested through the private message that I initiated. This will allow us to verify your profile. To access the private message, kindly click on the message icon under the "Question Info" as shown in the image below:

Please be advised that as per the register and schedule an exam page, effective January 16, 2023, you can have a maximum of two Microsoft Certification exams scheduled at a time, either on the same day or on separate days through Pearson VUE. You can schedule certification exams no more than 90 days in advance. You can reach out to the Pearson VUE support for additional information.
Moreover, we are doing our best to make your experience better and we would love to hear your insights by submitting your Feedback and Complaints online as this will help us and our exam delivery providers to improve your experience.
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 Messages. Thank you.
Sincerely,