Sftp repo filled up on a full LVM VG: ways to fix that?

I run a kopia sftp repo on a debian-12 server, the repo is on a filesystem on a LVM LV.
The LVM VG is fully used already, no blocks available.
Now kopia ran out of space there …

What options do I have to fix that? I’d like to reduce the number of kept snapshots but as far as I see I can’t do much as long as the repo has no free space. Is that correct?

I can think of temporarily adding some block device, maybe even a USB stick … to get things moving. I’d appreciate any helpful tips though, especially as I don’t have physical access to that server right now.

EDIT: I was able to fix it by resizing another LV and “moving” 1 GB of space over to the repo.