have ext4 fs and hangs on removing a snapshot

I've used it for a bit now on my ext4 /home dir. I mount an nfs share to snapshot to.
It seemed to used to keep only 2 snapshots automatically. I manually run it when i want.
I notice now 4 snapshots when i try to remove the old one the program just hangs.
is there a manual way I can remove this older snapshot so it will stop hanging?