Linz,
It looks like there's still a bit of water in the door. Check the "fluff trap" for want of a better word,and that it is draining properly, ie no kinks in the hose etc. Usually,most washing machines take a couple of minutes to equalise the pressure, after pumping out the water,to release the suction seal around the door.It should then open,if your machine isn't draining properly,then the vacuum seal won't break,keeping the door shut. Either that,or it's kapput! Best I can do,don't force it,get a bigger hammer........ Ree