only 800#.
try
https://intuit.taxaudit.com/
however, the ability for anyone to help is dependent on what the notice says and your access to documentation to support your position.
probably a more expensive option would be to work with a US law or CPA firm that has an office in the country in which you are currently residing. but again they may need documents to support an appeal to the IRS.
if you could provide general info about the issue without personal info, we could advise you of whether or not to pay up or not
with the 5564 you should have received form CP3219A
why you got the notice:
the IRS received information that is different from what you reported on your tax return. This may result in an increase or decrease in your tax. The notice explains how the amount was calculated, what to do if you agree or disagree, and how you can challenge it in U.S. Tax Court, if you choose to do so.
What you must do
Read the notice carefully. It explains the proposed increase or decrease in your tax. Note: The amounts shown as due on the enclosed Form 5564, Notice of Deficiency – Waiver, may not match your previous notice amount due because you can't challenge all items in U.S. Tax Court.
You can submit your response by:
Mail using the return address on the enclosed envelope, or
Fax your documents to the fax number in the notice using either a fax machine or an online fax service. Several online fax services use the internet to send files from your computer or smart device to a fax number.
If you agree with the changes, sign the enclosed Form 5564 and return it to us.
If you don't agree, you have the right to challenge the proposed changes by filing a petition with the U.S. Tax Court no later than the date shown on the notice. Please note the court can't consider your case if you file the petition late.
If you don't agree with the changes and have additional information for us to consider, mail or fax the information with the enclosed Form 5564 to the address or fax number on the notice. Our review of the new information won't extend the time you have to file a petition with the U.S. Tax Court.
