Extract p12 or private key from imported certificate

Hi Community,

I have the following Problem:

A customer needs an SSL-Certificate renewed, that is only used for XG (Webserver, Userportal, Webadmin). For this i need the private key. A collegue renewed it last year und uploaded it on the Sophos XG, unfortunately he is no longer part of the company.

I assume he exported the old certificate, extracted the key, created the new p12 file and uploaded it. You can't do this anymore since 18MR5. No keys to be found in our documentations.

EDIT: Appliance: Sophos XG230 SFOS 18.5 MR1

So the question is:

Is there still a way to extract the private key from the CLI?

Any help would be greatly appreciated.

Kind regards,

Olli