E15 error code means water has leaked into the base and has activated the flood switch in there.
What you need to do is pull the dishwasher out and lay it on its back and this will allow the water to drain out from the base. So you will need a towel for that part.
Once the water is out the flood switch will reset itself and this will clear the error code.
Then retry it and fingers crossed this is just a one off that caused it.
But if it does it again then theres a leak under there which you need to find and fix. For this you need to remove both side panels and then you can see the workings under there and check for any loose hoses.
Try that and see how it goes from there and let me know.
Nice one hopefully thats sorted now.
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