GTP says I'm a Resident Alien but I don't have a Permanent Resident Card (Green Card)

A Resident Alien for U.S. tax purposes is NOT the same as a Permanent Resident Alien. A Permanent Resident Alien is an immigration status whereby the individual has been granted permission to live and work in the U.S. for the rest of his or her life. A Resident Alien for U.S. tax purposes simply means that you have been in the U.S. for a long enough period of time that you will be treated in the same manner as a U.S. citizen – it does not confer any immigration privileges, it simply has to do with tax issues.

As a Resident Alien for U.S. tax purposes, you must file your tax return in the same manner as a U.S. citizen; GTP is only for use by Nonresident Aliens for U.S. tax purposes.