Hi pmehta, this question does come up from time to time. Please have a read through this at let me know if you find this helpful.

Negative amount shows that there is tax overpayment. The most common causes of this are:

• Incorrectly tax rate.
• You've deleted a paycheck after the tax payment was approved for the payroll period.
• Incorrect reconciliation of historical taxes.
• A duplicate tax payment was made.

The steps you need to follow depends on the reason of the overpayment. You can check out these articles for more details:

• Resolving a tax overpayment
• Resolve tax overpayments or underpayments

That should get you on the right track :)