Nationwide Grant Company Calling many times every day ripoff Cincinnati Ohio

Sorry for my English...
Last two weeks every day I get calls from representatives of Worldwide Grant company, and decided to search Internet about this company and Government Grant program.
Looks like this company has a bad reputation and a lot of people lost money, because they trust on their words...
Callers represented himself as a worker with 'Nationwide Grant Company'. Their accent seemed to indicate they were of Indian or Pakistani origin. They stated, by phone, that the U.S.Government had selected me and was awarding me (free of any charge and taxation) a Personal Grant from 6000 to 50000.00 dollars... to be deposited directly in my checking account after 5-7 days.
They had my name and address. They ask me to tell my last 4 digits of my SSN and then they ask me about my bank account number...
Here I began ask questions about why they need my account number, if they will be sent me a Grant check, and I can deposit this money by my self to my account. I didn't give any information about my account, and I think it was best for me.

Today again I got call from same company. I ask them to give me a name of company, and contact information: email address, website, name of their boss. Name of company - Nationwide Grant Company. Name of boss is Richard Micle. After I tell them never call me again.

What do I have to do if they will be call me again?
Thanks for advice.

Valentina
Cincinnati, Ohio
U.S.A.