CONSTANT SPAM SALES CALLS!

I have been receiving NON STOP spam sales calls from African bank for the past 3 days. Most of them heavy breathing on the other side and then an agent wanting to know if I am interested blah blah. No matter how many times I block your numbers, your agents phone from MULTIPLE NUMBERS starting as early as 8am. I am NOT an African Bank client AND I DON'T WANT YOUR SERVICES!!!!! You need to stop harassing me!!!