Not sure if you got my first post so here it is again.
Since you have unplugged the unit a few times and that did not cure the problem it will require parts to fix the problem :(
The problem will either be with the lock being broken (a common issue with this model) or a bad control board.
The only way to be sure is to run the diagnostic program. Below I have included a copy of the tech sheet, You would follow the instructions for running the diagnostic program, Once the program has run you will be given a error code, Look this up on the sheet, this will tell you where the problem is and the corrective actions needed.
If as I suspect you have a bad lid lock you will need to replace it.Click here to download the tech sheet
I have also included a link below where you can buy the part, if you scroll down the page you will see a video that will show you how to replace the lock also :)
To order your replacement part>>>>> CLICK HERE <<<<< To order your replacement part.
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