There is still time before the deadline.
Student or Learner
Normally the company will release bonus 2 weeks before end of February.
This year doesn't.
Why so long haven't give the bonus yet?
How should I use how long in the question?
Normally the company gives out bonus two weeks before the end of February but not this year. What is taking them so long? Why are they delaying the bonus?
Your 3rd line sounds like a translation in Chinese which does not work in English.
not a teacher
Is it wordy to say 'After such a long time, why haven't they given the bonus yet?
Not a teacher.
If, historically, the bonus is given 2 weeks before the end of February, then it's not yet late. It will be late if it hasn't been paid by February 15th. At that point, you could say "Why is the bonus late this year?" or "Why haven't we had our bonus yet?"
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.