Sounds like foreigner representing US govt. offering grant/irs revenue options. Very rude and unproffesional. I keep putting numbers on reject list but they keep coming.

Calls my cell phone often. When I answer, the line is silent. Then the call disconnects.

I'm going to end up changing my number because of this. Calls once a day,
I answer, no one is there, call it back, says it's invalid.

Should you change your phone number please remember this. Your new number is someone else old number. And they got rid of it for a reason. You may find your new number is worse. Please consider a call blocking device, or cell app. The $40. cost will save you years of misery.