@Ty412
Thank you for posting in Microsoft Q&A forum.
Failed to get client certificate for transportation. Error 0x87d00280
It seems it's related to HTTPS configuration on your site. Are you using HTTPS mode for your site? Check if you are choice the HTTPS only from the properties of the site server. If you use HTTPS, HTTPS requires the client and site system roles to be configured with valid PKI certificates for mutual authentication.
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