supervisor: Can't add network storage (mountin did not succeed)

The problem

I’m trying to connect to a netwokr share but this fails.

What version of Home Assistant Core has the issue?

core-2023.6.0

What was the last working version of Home Assistant Core?

No response

What type of installation are you running?

Home Assistant OS

Integration causing the issue

No response

Link to integration documentation on our website

No response

Diagnostics information

No response

Example YAML snippet

No response

Anything in the logs that might be useful for us?

Logger: homeassistant.components.hassio
Source: components/hassio/websocket_api.py:125
Integration: Home Assistant Supervisor (documentation, issues)
First occurred: 2:46:04 PM (19 occurrences)
Last logged: 3:37:33 PM

Failed to to call /store -
Failed to to call /mounts - Mounting backup did not succeed. Check host logs for errors from mount or systemd unit mnt-data-supervisor-mounts-backup.mount for details.
Failed to to call /mounts - Mounting ha_backup did not succeed. Check host logs for errors from mount or systemd unit mnt-data-supervisor-mounts-ha_backup.mount for details.
Failed to to call /mounts - Mounting habackup did not succeed. Check host logs for errors from mount or systemd unit mnt-data-supervisor-mounts-habackup.mount for details.
Failed to to call /mounts - Mounting backups did not succeed. Check host logs for errors from mount or systemd unit mnt-data-supervisor-mounts-backups.mount for details.

Also checked logs trough terminal, same line but with date and time.

Additional information

Tried various names for the network storage in HA, Remote hare and username, with and without special characters. Also tried different passwords, with and without special characters, long and short (8chars).

Shot sure hot to perform “systemd unit mnt-data-supervisor-mounts-backups.mount”. Have tried in terminal, but systemd does not seem to exits?