Measure behaving weirdly?

Hi,

I have a simple measure that is working fine when I add it into graph or table, but when I use it in a card, it is showing blank.

Snapshot in the following link https://ibb.co/KGHVVBT

(Sorry didnt know how to attached an image here)

I have other measures, using the same formula and is working fine.. But why this one is not working

Thanks,