Without the information requested in my previous response, I can only give you a general answer, but I hope this helps.
Please leave it unplugged for around 1 hour.
Then press and hold first button on left and extreme right buttons together.
Keep them held in and then plug it back, let go off these buttons after around 15 seconds.
Then turn it on turn it back off then turn it back on and see if this will reset the appliance.
However, if the error is still there then I am afraid you will have to contact the manufacturer and get the control board replaced.
I hope this helps, please do not hesitate to ask any follow up questions.
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