What's wrong with my dishwasher?

[Bejazzled]

The bottom tray front right all of a sudden isn't washing properly (the rest of it seems to be ok)
I've cleaned the filters and the whirly spray thing but it's still not right ☹️

Are you sure you're not stacking it with something sticking down which prevents the whirly arms getting round?

Lemon pip in the ends of the whirly thing?

This can happen with a hole in the cutlery basket. Something points down and obstructs the washing arm.

Pull the whirly arms out and shake the encrusted shit out of the holes. You may need to use tweezers to pull lemon pips, corn or red peppers out, sometimes fossilized bits of pasta. You could find it beneficial to give it a wash cycle with some bicarbonate soda in and some vinegar in the rinse aid bit as well.

Right, I shall check all of the above - thank you!