I765 interview is scheduled after getting green card already

[dracula224]

Hello,

I got my green card back in Dec 2019 but just received a letter that says my I765 (work permit) application is scheduled for Feb 7.
My questions are:
1/ I did not know there is an interview for I765 application. I thought interview only for I485?
2/ Why do I need to continuous with I765 as I already have green card which allows me to work legally. Should I just ignore this letter or try to contact to cancel the interview?

I am really confused. Please help to clarify. Thanks a lot.

[Enub4]

It is better to not ignore anything that USCIS sends you even by mistake. It is your responsibility to respond and fix the situation. You need to call them.

What does the letter say? Date and time for an interview? What documents do they ask you to bring? This is the first time I read about an I-765 interview.