There's water in the base of the machine, not inside where you put the dishes, below that.
Unplug the appliance.
Empty it and drag the machine out.
Put towels at the rear of it and tilt the machine rearward to drain the water out of the base.
Once empty, stand the machine up and try it again.
If all is ok, it will be working.
If there's a leak, it will begin working then fail the same again.
In the case of a leak, you need the side panels off so you can watch the machine working.
Locate and cure the leak to rectify the fault.
(On some AEG machines, there is a panel below the door that you can take off.
You can use a sponge or similar to remove the water from there. Do unplug the machine first though).
Obviously, if you cannot do the work yourself, you'll need to get someone in to do it for you.
Hope this helps