my beco wmb 10w.isn't washing properly its goes threw the cycle but it isn'?

beco wmb 10w isn't washing properly can anyone help please .
it goes threw the cycle but it isn't washing properly .the drum goes round once then stops then after a minute goes round once again. it goes threw the cycle and empty then goes onto spin and does the same as when on the wash goes round once then stops then after a minute goes. round once.
it works like this every time its got me baffled can Amy one give me any advice As what it can be ? please .