Most washing machines have a filter that the consumer can access. Sometimes in plain view or hidden behind an obvious flap in the lower regions of the front panel. Built in, integrated washing machines and washer dryers have a filter that is hidden by the kitchen unit plinth, making it much harder to access. 

Once you have found the filter, your instruction book will usually let you know where it is, it's again fairly obvious that if you pull the filter out you'll get lots of water on the floor. So take precautions, undo the filter slowly, control the water flow and have something to hand to mop up and clean up as your doing it.

Lint filters catch all sorts of debris from a wash, coins, combs, credit cards.......... whatever you leave in the pockets will make its way down to the filter. Releasing the water allows you to check if the filter was blocked, causing the water to not empty under the pump action.

If this course of action does not solve the prroblem, then any of the following might apply:

1) blocked drain hose and or sink unit

2) defective drain pump

3) blocked and restricted lower sump hose

4) Eco ball in the sump hose jammed

5) washing machine overfilling with water

The question, "my washing machine is not draining?" can be several different causes, but the easiest one is to check your filter, it shouldn't involve an engineer.