If you have not filled in a new W-4 in the last 4 years then the result you are getting is to be expected as the new withholding system is meant to keep your refund on your return as close to zero as possible. On the W-4 you can (A) choose the SINGLE filing status OR (B) don't claim the child OR (C) enter an amount on line 4C to force more being withheld OR do more than one of these things. Review your refund from the prior year ... did you get back most or all of your withholdings in the past ? If so then you may not need to have withholding ... just be aware that your refund will be less.
