Hi @raj a ,
but I have renewed & installed the new cert on server & also assigned services like IIS,POP,IMAP & SMTP to it
How did you renew and install your certificate? By those steps as the official document mentioned or others? We recommend you follow the steps above to renew your certificate.
found the new SSL certificate over there (In address bar)
Do you mean you could find the new certificate in your certificate list? If so, what's the status of your new certificate? Please ensure that your certificate is valid after you complete the renewal.
In order to further ensure the services were assigned normally, we could try to re-assign them via EAC or Exchange management shell as the document mentioned to check if the issue has any difference after that.
If the response is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.