With the extra amount, is it better to repay debt or keep it as savings?

Pay $1200 to your creditor and keep $800 in your emergency fund.

So, now you have $2000 in your wallet??
It's better to save the money that you got as a bonus ($800), and reduce your debt amount by using the saved amount ($1200)

Paying off the credit card balance will help you avoid interest payment in the next month. So, try to clear the debt and save the remaining amount. From the next month, plan a budget and try to save a substantial amount.

Use the bonus to repay your credit card debt. Try to get out of debt as soon as possible, credit card interest is high, you will lose your money on paying the interest rate. So, get rid of them soon,

Your first priority should be getting rid of your debt. What you can do is make payments of $1500 and save $500. So you can make 2 shots with one bullet!