3rd party Certificate

Hello,

Has anyone successfully replaced their self-signed cert from Symantec with a 3rd party cert?

I followed this article:  https://www.symantec.com/connect/articles/sep121-creating-and-using-3rd-party-ca-signed-cert-client-communications

but the response that I received from my Cert group is that the keylength size is not 2048.

I've already opened up a case with Symantec and not getting much help from them.

Is there a way to specify the keylength size when generating the CSR?