When a new user certificate for the SMPE internet service retrieval is needed, it's possible to download it from the this link:
https://eapi.broadcom.com/receiveorder/getSignedCert
But it could be there is an issue with getting the new certificate and get this message:
This message appears:ERR_INVALID_RESPONSE
Common Components for z/OS 15.0
SMPE Retrieval Service
SMPE Order service
To get a certificate, it's needed your Broadcom support userid is registered to a siteid with products licensed.