May I assume that you receive a letter from the IRS asking for form 8962?
If so, the letter contains explicit instructions on what the IRS wants from you and how you are to send it back. Don't send in the amended return (which you had to create in order to create the 8962), unless that letter explicitly tells you to.
Also note that some versions of that letter give you a fax number and tell you that you can fax the 8962 or mail it.
Always do what the IRS letter tells you and only what the IRS letter tells you.
