You do not give enough information. If it was a deficiency for trust fund taxes (payroll) then you are on the hook personally. If you can no longer as agreed then contact them and tell them your circumstances have changed and you need to work something out with a lower payment.
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Mr. Corrigan is correct - depends on the type of tax. If these are, for example, payroll taxes (Form 941, 944), and you are the "responsible person" then you are on the hook personally for the "trust fund" portion.
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If your corporations owes Form 940 or Form 941 taxes, then you would want to pay at least the trust fund portion of the payroll taxes, because the IRS can find you personally liable for that portion of the unpaid payroll (941 and 940 taxes).
As the other attorneys have stated, there are not enough facts here to properly answer your question.
This material does not constitute tax, legal or accounting advice. It was not intended or written for use and cannot be used by any taxpayer for the purpose of avoiding any IRS or NYS penalty. The information contained herein is for informational purposes only as a service to the public, and is not legal advice or a substitute for legal counsel, nor does it constitute advertising or a solicitation. This response is not intended to create, and does not create, an attorney-client relationship between you and the author.