I have twice ordered the new locking part for a Beko DW686 dishwasher. It goes in easily and works perfectly when I push the catch down manually before fitting. However, whilst I can use the washer by ramming a chair up against it, it won't lock. It seems the loop/catch at the top must be engaging it, as the washer only comes on when I press it in, meaning the connection has been made. In summary, the door shuts if you push it and turns on the washer, but the door falls straight open again if you don't hold it or wedge it. What can I do??