Thanks for that.
E15 indicates water has leaked in the base of appliance and activated the anti-flood device.
You will have to unplug the appliance and pull it out.
Then tip it backwards by around 45 degrees so excess water drains off completely.
After this is done, check the drain hose where it connects to house drain and make sure it is not clogged.
Then clean the mesh filter from inside and make sure it is not blocked.
Reconnect everything and plug it back.
It should work however, if the problem occurs again you will have to check what is causing the leak.
If you have any further questions, please do not hesitate to ask!
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