Is this the smart box with aerial connection?
Its a long shot, but have ytou tried putting it back to factory settings? This sometimes squashes any bugs that are on the system.
This link gives some troubleshooting, might help but might not.
One of its suggestions is to turn the router off for a bit then back on.
Worst case pop onto Live chat and they might be able to work something out.
Best to maybe jump onto Live chat and report the fault. Use the link on the post above yours.