What should I do with my government travel card when I ETS?

I'm pretty sure I still have mine floating around somewhere (obviously long expired). No one ever asked for it.

Use it? Isn't it in your name?
Do be sure to pay it off because the services will tell them where you live and if you don't it's stealing. Maybe after you pay it off just close it using the phone number on the back then cut it up.

The unit GTCC manager should have contacted Citibank and had the account placed inactive because the government will no longer be acting as a guarantor. But the account is in your name so keeping the account open can help with your credit score if needed since it is available credit even if you can't use it.