How Do You Fix an Electric Blanket That Displays 'E'?

Hi,
I have a kingdom electric blanket. The error code says 'E'. I've had my electric blanket for a few years. Now it says 'E'. I've unplugged it & waited for 8 hours at least but still says 'E'. I've never had this issue.

When turn it on, it flashes quickly 'H' then goes 'E'. You can't stop the 'E' or turn off the power. I have to unplug it only to stop the 'E' display. What do I need to do?