Who called from 3157085553

I am to receive a grant from the US government for $1,700 and I dont have to pay it back. When was the last time the government gave away money?

I am allowed to have my phone at work, but it's required to be turned to buzz.  This number keeps calling me repeatedly all through my work day and it's my workplace.  I never gave anyone my phone number, I have a bogus number I use on anything on the internet.  However they got my number, it wasn't from me.