I want to offer bounty to a question and the question already have a bounty. Can I add additional bounty for the question? Also the question is not asked by myself.
Can I raise my bounty?
You can offer as many bounties on a question as you want. However, only one bounty can be active on a question at a time. Moreover, any user may have at most 3 concurrent bounties at a time.
Can I add additional bounty for the question?
As in adding to the total? No.