Endless calls

I was called about 15 times in one afternoon by this company. I was in meetings and declining calls every few seconds. I eventually answered the call to tell the woman to leave me alone. I don't care how much money I could/might/would save when I'm harassed like this. This is still ongoing. When I reject calls I get called back in a few seconds. The only way I get a short reprieve from the harassment is by answering and muting the calls. This seems to decrease the number of calls I receive a bit. I've explicitly asked to be left alone.