Can't access hometroller sel web interface

I have a hometroller sel which has been working perfectly for months but today it's web interface seems to have stopped working. It's also stopped running all events etc.

When i try to connect to it's local ip address on my local network it is not found. MyHS can't find it either. I can connect via filezilla and browse the file system but not via a browser.

Any ideas on how I can regain control?

Thanks