Snap does not start after reboot

Changes:

ID   Status  Spawn                Ready                Summary
35   Error   today at 05:04 CEST  today at 05:05 CEST  Auto-refresh snaps "wpe-webkit-mir-kiosk", "mir-kiosk"
46   Done    today at 11:07 CEST  today at 11:07 CEST  Running service command
49   Done    today at 11:24 CEST  today at 11:24 CEST  Disable "wpe-webkit-mir-kiosk" snap
51   Done    today at 11:26 CEST  today at 11:26 CEST  Enable "wpe-webkit-mir-kiosk" snap

The last three were initiated manually by the affected user upon request.

snap tasks 35 output
Status  Spawn                Ready                Summary
Done    today at 05:04 CEST  today at 05:05 CEST  Ensure prerequisites for "wpe-webkit-mir-kiosk" are available
Undone  today at 05:04 CEST  today at 05:05 CEST  Download snap "wpe-webkit-mir-kiosk" (25) from channel "stable"
Done    today at 05:04 CEST  today at 05:05 CEST  Fetch and check assertions for snap "wpe-webkit-mir-kiosk" (25)
Undone  today at 05:04 CEST  today at 05:05 CEST  Mount snap "wpe-webkit-mir-kiosk" (25)
Undone  today at 05:04 CEST  today at 05:05 CEST  Run pre-refresh hook of "wpe-webkit-mir-kiosk" snap if present
Undone  today at 05:04 CEST  today at 05:05 CEST  Stop snap "wpe-webkit-mir-kiosk" services
Undone  today at 05:04 CEST  today at 05:05 CEST  Remove aliases for snap "wpe-webkit-mir-kiosk"
Undone  today at 05:04 CEST  today at 05:05 CEST  Make current revision for snap "wpe-webkit-mir-kiosk" unavailable
Undone  today at 05:04 CEST  today at 05:05 CEST  Copy snap "wpe-webkit-mir-kiosk" data
Error   today at 05:04 CEST  today at 05:05 CEST  Setup snap "wpe-webkit-mir-kiosk" (25) security profiles
Hold    today at 05:04 CEST  today at 05:05 CEST  Make snap "wpe-webkit-mir-kiosk" (25) available to the system
Hold    today at 05:04 CEST  today at 05:05 CEST  Automatically connect eligible plugs and slots of snap "wpe-webkit-mir-kiosk"
Hold    today at 05:04 CEST  today at 05:05 CEST  Set automatic aliases for snap "wpe-webkit-mir-kiosk"
Hold    today at 05:04 CEST  today at 05:05 CEST  Setup snap "wpe-webkit-mir-kiosk" aliases
Hold    today at 05:04 CEST  today at 05:05 CEST  Run post-refresh hook of "wpe-webkit-mir-kiosk" snap if present
Hold    today at 05:04 CEST  today at 05:05 CEST  Start snap "wpe-webkit-mir-kiosk" (25) services
Hold    today at 05:04 CEST  today at 05:05 CEST  Clean up "wpe-webkit-mir-kiosk" (25) install
Hold    today at 05:04 CEST  today at 05:05 CEST  Run configure hook of "wpe-webkit-mir-kiosk" snap if present
Hold    today at 05:04 CEST  today at 05:05 CEST  Run health check of "wpe-webkit-mir-kiosk" snap
Done    today at 05:04 CEST  today at 05:04 CEST  Ensure prerequisites for "mir-kiosk" are available
Done    today at 05:04 CEST  today at 05:04 CEST  Download snap "mir-kiosk" (2132) from channel "stable"
Done    today at 05:04 CEST  today at 05:04 CEST  Fetch and check assertions for snap "mir-kiosk" (2132)
Done    today at 05:04 CEST  today at 05:04 CEST  Mount snap "mir-kiosk" (2132)
Done    today at 05:04 CEST  today at 05:04 CEST  Run pre-refresh hook of "mir-kiosk" snap if present
Done    today at 05:04 CEST  today at 05:04 CEST  Stop snap "mir-kiosk" services
Done    today at 05:04 CEST  today at 05:04 CEST  Remove aliases for snap "mir-kiosk"
Done    today at 05:04 CEST  today at 05:04 CEST  Make current revision for snap "mir-kiosk" unavailable
Done    today at 05:04 CEST  today at 05:04 CEST  Copy snap "mir-kiosk" data
Done    today at 05:04 CEST  today at 05:05 CEST  Setup snap "mir-kiosk" (2132) security profiles
Done    today at 05:04 CEST  today at 05:05 CEST  Make snap "mir-kiosk" (2132) available to the system
Done    today at 05:04 CEST  today at 05:05 CEST  Automatically connect eligible plugs and slots of snap "mir-kiosk"
Done    today at 05:04 CEST  today at 05:05 CEST  Set automatic aliases for snap "mir-kiosk"
Done    today at 05:04 CEST  today at 05:05 CEST  Setup snap "mir-kiosk" aliases
Done    today at 05:04 CEST  today at 05:05 CEST  Run post-refresh hook of "mir-kiosk" snap if present
Done    today at 05:04 CEST  today at 05:05 CEST  Start snap "mir-kiosk" (2132) services
Done    today at 05:04 CEST  today at 05:05 CEST  Clean up "mir-kiosk" (2132) install
Done    today at 05:04 CEST  today at 05:05 CEST  Run configure hook of "mir-kiosk" snap if present
Done    today at 05:04 CEST  today at 05:05 CEST  Run health check of "mir-kiosk" snap
Done    today at 05:04 CEST  today at 05:05 CEST  Consider re-refresh of "wpe-webkit-mir-kiosk", "mir-kiosk"

......................................................................
Setup snap "wpe-webkit-mir-kiosk" (25) security profiles

2019-09-17T05:05:19+02:00 ERROR cannot setup mount for snap "wpe-webkit-mir-kiosk": cannot update mount namespace of snap "wpe-webkit-mir-kiosk": cannot update preserved namespace of snap "wpe-webkit-mir-kiosk": cannot update snap namespace: device or resource busy
2019-09-17T05:05:19+02:00 ERROR cannot update mount namespace of snap "wpe-webkit-mir-kiosk": cannot update preserved namespace of snap "wpe-webkit-mir-kiosk": cannot update snap namespace: device or resource busy

......................................................................
Consider re-refresh of "wpe-webkit-mir-kiosk", "mir-kiosk"

2019-09-17T05:05:28+02:00 INFO No re-refreshes found.
snap tasks 46 output

Status Spawn Ready Summary
Done today at 11:07 CEST today at 11:07 CEST restart of [wpe-webkit-mir-kiosk.browser]

snap tasks 49 output

Status Spawn Ready Summary
Done today at 11:24 CEST today at 11:24 CEST Stop snap “wpe-webkit-mir-kiosk” (19) services
Done today at 11:24 CEST today at 11:24 CEST Remove aliases for snap “wpe-webkit-mir-kiosk”
Done today at 11:24 CEST today at 11:24 CEST Make snap “wpe-webkit-mir-kiosk” (19) unavailable to the system
Done today at 11:24 CEST today at 11:24 CEST Remove security profiles of snap “wpe-webkit-mir-kiosk”

snap tasks 51 output

Status Spawn Ready Summary
Done today at 11:26 CEST today at 11:26 CEST Prepare snap “wpe-webkit-mir-kiosk” (19)
Done today at 11:26 CEST today at 11:26 CEST Setup snap “wpe-webkit-mir-kiosk” (19) security profiles
Done today at 11:26 CEST today at 11:26 CEST Make snap “wpe-webkit-mir-kiosk” (19) available to the system
Done today at 11:26 CEST today at 11:26 CEST Setup snap “wpe-webkit-mir-kiosk” aliases
Done today at 11:26 CEST today at 11:26 CEST Start snap “wpe-webkit-mir-kiosk” (19) services
Done today at 11:26 CEST today at 11:26 CEST Automatically connect eligible plugs and slots of snap “wpe-webkit-mir-kiosk”


Make snap “wpe-webkit-mir-kiosk” (19) available to the system

2019-09-17T11:26:30+02:00 INFO added auto-connect task