Partial digital display?

The LED display is only partial. Most of the time the fridge and freezer temperature displays do not show all of the parts of the digits. After googling, I've pressed buttons to get the error codes.

If I press the top 2 buttons (power freeze and lighting) for about 10 seconds, all of the LED lights up, followed by an error code.
_ _ _
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_|| |_| |

so it looks like a digital 9 followed by the left bottom and top right vertical bars
and then it is a digital 8 followed by the top horizontal bar and bottom left vertical bar

It appears to be working fine, and as far as we can tell, the display is the only thing wrong.

Any ideas please? I've had this Samsung American style fridge freezer for about 4 years.

Thanks

Janey
June 2015