Answer:
It is a form of plastic money.
What falls down but never breaks?
Mouth up it gets filled, mouth down it gets empty.
What is often on the ground getting stepped on by others, but you donโt have to wash it because it never get dirty, in fact you couldnโt wash it even if you tried?
How do you spell hard water with only three letters?
If itโs information you seek, come and see me. If itโs pairs of letters you need, I have consecutively three. What am I?