Hotpoint Aquarius WD62 – door opening mid-cycle

Fortunately the Washing Machine is outside (in a conservatory with tiled floor) – but the last couple of times we’ve put the washing machine on the door has opened before the cycle has finished.

Of course I blamed my wife for not shutting the door properly or putting too much in (but I actually don’t think it could be either of those things?).

Any ideas what the problem could be? I’m probably going to change the door interlock – I’m guessing that’s a good starting point?

Thanks.

Tony.