This question already has an answer here:
I never had a single issue with yosemite, until yestersday after updating to 10.10.2.
Now I press a key and hold it and it is not repeating anymore.
but the problem is selective. Spaces repeat. Symbols, punctuation mark repeats but numbers and letters don't.
Any way to make that work again?
Nope, that is set (look pic).