Why does the conditioner not go through the system Servis W/machine M6503S?

We have had the above W/M for approx 3 years.
When we use No 3 dispensing tray for conditioner it does not go through the system, we have cleaned it out many times but it is still not going through thereby clogging the drawer. Also when the 'grid' is replaced after cleaning it looks like the hole that the conditioner goes out of is covered by the grid?