Deployed guix is dead?

[address@hidden]

Hi Guixers
I have a remote machine where I deployed a calendar server via guix deploy. A 
while ago the let's encrypt certificate expired (which I assumed will renew 
automatically?). I then tried to update the system with guix deploy, but always 
get the error guix repl -t machine failed with status #f. Connecting to update 
the machine via ssh and running (any) guix command results in the message 
killed displayed in the command line. Any idea what the problem is and how I 
can debug it?
Best,
Reza