I have tried to load a till roll tonight and get the"HEAD UP" message even though I have done this many times before. I reinserted the roll and pushed down the till roll bar securely but no difference.
What's gone wrong.

Also when programming some price change keys, I ended up with a minus result. How do I change this in the program mode?

Hi. You forgot to press CLEAR after changing the roll. On Sharps, you must clear the error to continue no matter what error is on the display.

When you say minus, do you mean the item has a negative price after programming or everything is displaying as negative. Please tell me what you did during programming.