Please Help Me Connect My Vaultpress Again

I recently had a problem with backing up data from Vaultpress. And I sent support requests to them, did they tell me the following:
"Reach out to your webhost to first make sure that VaultPress is not getting blocked or limited or is prevented from increasingly your xmlrpc.php file. They can check their error logs for 403 errors to see exactly what’s happening. For the best results, you could also have them whitelist the VaultPress IP ranges noted on this page: "
Please help me fix this my problem
Thank you very much

Please don’t double-post.