Where is this slider you are trying to move, which UI?
Is your xxx.things file loading - should be a message in your openhab.log?
What related messages do you see in your events.log and openhab.log, if any?
Binding is installed, thing is online. I try in Paper UI
Below logs from openhab.log
2020-07-21 09:35:25.135 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'exec.items'
2020-07-21 09:37:11.857 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'execute.things'
Additionaly I changed switch status by rule. Below output in openhab.log:
2020-07-21 09:40:05.016 [ome.event.ItemCommandEvent] - Item ‘Backup_Run’ received command ON
2020-07-21 09:40:05.063 [vent.ItemStateChangedEvent] - Backup_Run changed from OFF to ON
2020-07-21 09:40:05.153 [vent.ItemStateChangedEvent] - Backup_Run changed from ON to OFF
Okay, that’s different. There are a hundred things that can go wrong, usually about permissions.
You could at least temporarily link more Items to Thing output, exit, and lastexecution channels, to gather more clues.