They passed me an old .key file and the new certificate.
With the right key everything is working now.
Ok I debugged.
When saving the new ssl certificate (cert, key and bundle), ispconfig restarts apache.
It fails and reverts to old file.
I can't find the error log.
In this path is empty:
today I tried to update the ssl cerficiates in Ispconfig.
I saved and from ISPconfig I see the new one.
But then I checked and the system...
Separate names with a comma.