I called back to the number and find out that is a massage shop's number, may be 'more than just massage' based on the tone the automated woman voice answering the phone. Please tell me how I can stop this 'shop' to call my number.

I repeatedly got a call from this toll-free number to my cellphone. I usually give my number to family and friends only. I did not answer the calls from this toll-free number. However, I was really bothered by the calls from this number. How can I stop this?