can't access package repositories with git+ssh

[Mario Ceresa]

Hi everybody!
Sorry if it is a stupid question, but since I changed my ssh key
yesterday I'm not able to use the package repository anymore. It
always says:

[mario@gervis gdcm]$ fedpkg push
ssh_exchange_identification: Connection closed by remote host
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
Could not execute push: Command '['git', 'push']' returned
non-zero
exit status 128

I can ssh to fedorapeople.org with the new key, so it is not a sync
problem, right?

Thanks for any hints and Happy Easter!

Best,

Mario