HD channels have stopped working

[Rosemary4]

My HD channels have stopped working on one of my Sky+HD boxes. I have a sky HD subscription but the channel is asking me to upgrade, I've tried restarting the box but nothing happens. 

[Mr+Flibbles+86]

Hi there @Rosemary4 , I’ve escalated your post to our Community Messaging team who will invite you to a private chat shortly and help you with this. 

Just look out for the colourful bubble to start the conversation.

Here's more information on how Community Messaging works - https://helpforum.sky.com/t5/Did-you-know/Escalating-a-post-to-a-Sky-expert/ba-p/3711147