After purchasing an SSL certificate in Plesk, the certificate cannot be issued with the message:
Could not issue your certificate
There was a problem issuing your certificate. See below for more details.
Performing domain validation (by HTTP or e-mail)
Your domain did not pass a domain control validation (DCV). To fix the issue, change the DCV method or follow the troubleshooting recommendations.
The domain validation has not been completed.
The instructions to complete the domain validation are available on the SSL certificate provider's website - сlick on the link change the DCV method or follow the troubleshooting recommendations and follow the instructions. Choose any convenient for you method to complete the validation.