Home Assistant Update is failing on Synology VMM installation


First of all big thanks to all your support.

I have Synology NAS 920+, i have followed steps mentioned in following link.

My Home Assistant is up and running.
Now when when I try to update it is failing and can see following error.

22-05-03 23:32:51 INFO (MainThread) [supervisor.os.manager] Fetch OTA update from https://github.com/home-assistant/operating-system/releases/download/7.6/haos_ova-7.6.raucb
22-05-03 23:32:54 INFO (MainThread) [supervisor.os.manager] Completed download of OTA update file /data/tmp/hassos-7.6.raucb
22-05-03 23:32:56 ERROR (MainThread) [supervisor.os.manager] Home Assistant Operating System update failed with: Installation error: Failed updating slot kernel.1: failed to mount slot: failed to run mount: Child process exited with code 32

Please help me to solve this issue.
Thanks in advance.