I will guarantee for you that this number is not a scam, but a legit (granted horribly annoying) collection agency working for Macy's. I was getting so many calls from this number on my cell phone, out of the blue, asking for someone by another name. It got so bad that after a lot of web investigating, I managed to find a Macy's representative who said that YES, this is a Macy's outsourced number, and he would make sure that my cell phone number was removed from this person's account (I don't even have a Macy's account). Sure enough, the calls stopped.
You have two options- call Macy's, demand to speak to collections/complaints dept. (not customer service), and have your number taken off their list. OR, and I didn't need to go this far but found this out- you can contact the Federal Trade Commission who monitors the FDCPA (Fair Debt Collections Practices Act). There are specific laws regarding what collections agencies can and cannot do, and repeated calls are illegal.
I know this is wordy, but hope it helps. I was initially so stressed out by these calls- wasn't even sure if it was a scam or not, but rest assured that no matter what anyone says, this number IS a Macy's collection number. If you have an account with them, check it through a Macy's main line and if you don't, call Macy's to have your number removed.