Dear Apple Developer Support Team, I hope this message finds you well. I am currently utilizing the services at https://identity.apple.com for mobile device management and encountered an issue while attempting to upload a Certificate Signing Request (CSR) file to the portal. The system generated an error indicating that the file format was invalid. Below are the steps I followed to generate the CSR: I first created a private key on my server using the following command: openssl genrsa -out private.key 2048 Next, I generated the CSR file with the following command: openssl req -new -key private.key -out request.csr Despite following these steps, I could not successfully upload the CSR file and obtain the APNs certificate. I would greatly appreciate your guidance on creating and uploading a valid CSR file to avoid this error. Please let me know if there are any specific formatting requirements or additional steps I need to follow. Thank you in advance for your assistance and support.