Due to a recent change in policies and standards, multiple websites (including Paypal) are now requiring vendors and e-commerce sites use an SSL certificate signed with the SHA256 algorithm (also referred to as SHA2) and will no longer accept SSL certs signed using SHA1. As a result of this you may need to have your SSL certificate re-issued using the SHA256 algorithm.
To complete this, you'll first need to generate a new key/CSR pair through cPanel (make sure you use a 4,096bit private key). It's important that your new key/CSR match the exact same domain name you used for the original certificate: https://support.hawkhost.com/index.php?/Knowledgebase/Article/View/123/0/how-do-i-generate-a-csr--certificate-signing-request
Once your new key/CSR are generated, please open a ticket at https://support.hawkhost.com asking to have your SSL certificate re-issued. Be sure to include your new CSR in that ticket as our support team will need it to complete the re-issue.
Your certificate will then be re-issued using SHA256 (SHA2), at which point we'll also install your new certificate for you.