Have you tried a soft reset? To do this hold the power button on the front for around 10 seconds and the box should restart. Alternatively, you can turn off from the back and power back on.
If this doesn’t work then have you tried a YouView Maintenance Reset (https://community.talktalk.co.uk/t5/Articles/How-to-find-maintenance-mode/ta-p/1429347)?
Try the Factory Reset keep recording option.
You will then need to reset your personal settings (such as parental controls / RF loop through / Surround Sound etc.) and also reset your scheduled recordings (might be worth taking a note of future recordings before doing this so you don’t miss any).
Hope it works but if not then please let us know and I’ll flag for further assistance.
For a quicker reply can you please ensure you have your personal information up to date in your profile. Link here - https://community.talktalk.co.uk/t5/user/myprofilepage/tab/personal-profile:personal-info
If you are unsure of your phone number, you can find this in My Account or dial 17070 from your land line phone and this will confirm the number for you.
Thank you for your reply none if these worked still have no TV. I am on the phone with an adviser now who us trying to book me an engineer?? Surely easier to replace the box?
Plus now if engineer can not fix this then they order a new box so prolonging the time on which I am paying for tv that I do not have!
Unfortunately that's what you get when taking multiple routes to resolve an issue.
This forum would have resolved your issue without an engineer but as you have taken the route of phoning that it the solution on offer so you will probably have to see it through now.