how can i fix my thomson freeview box?

You are the 21st person to ask that question on howtomendit this month.

Top Up TV used to broadcast a 14 day programme guide, but permanently ceased broadcasting on 1st November 2013.

You need to change to the freeview 8 day guide.
Menu >> Set-up >> Change your box settings >> TV Guide Type
Use the < > keys to switch to the 8 day freeview guide.

Immediately after changing the setting to the 8 day epg a Top Up TV recorder owner should be patient. It can take a few hours before all the epg is populated without any gaps.

If you still have a card installed then one suggestion elsewhere is to also remove the card.

Good luck.

Neil S
November 2013