lxc backup

I'm getting a weird thing when I try to run a backup from an LXC container. If it's running, I get this error.
"/mnt/pve/Backup1/dump/vzdump-lxc-116-2025_09_02-17_29_31.tmp/root" failed: Permission denied (13)

ERROR: *** Skipping any contents from this failed directory ***

ERROR: rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1338) [sender=3.4.1]
ERROR: Backup of VM 116 failed - command 'rsync --stats -h --numeric-ids -aH --delete --no-whole-file --sparse --one-file-system --relative '--exclude=/tmp/?*' '--exclude=/var/tmp/?*' '--exclude=/var/run/?*.pid' /proc/3274853/root//./ /mnt/pve/Backup1/dump/vzdump-lxc-116-2025_09_02-17_29_31.tmp' failed: exit code 23
INFO: Failed at 2025-09-02 17:29:31
INFO: Backup job finished with errors
INFO: notified via target `mail-to-root`
TASK ERROR: job errors

But if I manually turn it off and run the backup while it's running, it works fine and gives no error, but I can't run a backup while it's on.

The thing is, it's running backup against an NFS drive.
Has anyone else experienced this and found a good solution?