sometimes the tube thingy that the conditioner should flow down gets plugged. Take the drawer apart and wash the components or run an empty machine on the hottest longest cycle you have with 2 dishwasher tablets in it might work instead.
Simple .... unplug the machine from the mains ...
Remove the detergent tray ...
Remove the top cover of the machine, and then remove the pipe below the tray...
Unclip it from the drum ... and then scrub it out using an old toothbrush and detergent with hot water.
Re-fit and secure screws..!
Being a husband, I'm not too well up on washing powders/materials but,once you've got the washer cleaned and working properly, would it be worth while suggesting that you try a different conditioner?????
possibly a drain pump needed - if so not expensive.
<a href="http://www.leedsappliances.co.uk">leeds appliances</a> should be able to help . 0113 3936690
Try using a powder/liquid containing conditioner, & add a couple of tablespoons of washing soda to each wash too as this helps soften the water & keeps the pipes fresh.