We have a domain called wift.com and this domain is using R3 certificate which is expiring soon. Unfortunately we don't have any information about the account which was being used to manage this certificate.
Is there any way that we can find out the account name or a procedure for how to extend the certificate?
The procedure is going to depend on where and how your website is hosted.
Your account credentials consist of a private key somewhere near the acme client that obtained the certificate. If you don't have access to that key, just make a new one.