This means the certificate you set up on your origin server needs renewing. You need to do that yourself.
The certificate isn’t replaced, that certificate is the one on the Cloudflare edge. Both that and your origin certificate are needed for the most secure configuration, see…
The 522 error means Cloudflare can’t connect to your server. Make sure you have set the new VPS’s IP address in your Cloudflare DNS, and that your VPS isn’t blocking Cloudflare’s IP addresses from connecting.