Extension rejected twice now due: R0000-679-01 - 'PrimPriorYrPIN' or 'PrimaryElecFilingPIN' or 'PrimPriorYrAGIAmt' in the Return Header must match the e-File database.

I can't fix the rejection error of your extension, but here is a link to Form 4868, Application for Automatic Extension of Time To File U.S. Individual Income Tax Return.  You can print it, fill it out, and mail it to the IRS.

https://www.irs.gov/pub/irs-pdf/f4868.pdf