Washing machine doesnt complete full cycle

washing machine gets to spin stage and makes small back and forth rocking noises/movement but doesnt drain properly or start spinning. I checked fault diagnostic lights and got the following. off,off,on,off,off,on,off,on. Also my last wash prior to this fault made the clothes muddy (is there a filter that needs cleaning or similar?) Could this be related to the incomplete cycle situation that now exists? Any help or direction towards diagnostic codes would be appreciated, Thanks.