Dishwasher top rack not cleaning

Dishes in the top rack not cleaning or drying. I have cleaned the bottom filter screen and check all arms for clogged ports. I am not sure the age of the machine.
The water temp and pressure is ok. What could the problem be.
Thanks

I’m sure a new in valve would have fixed it. When I cleaned the screen it was better. However I have purchased a new washer. I did not want to put more money in it. Found a good deal with a veterans discount.
Thanks for your help.