Although most telemarketers should avoid calling a number after it has been on the National Do Not Call Registry for more than 31 days, some telemarketers still do. In that case, a user can submit a complaint on DoNotCall.gov, even if telemarketers used a recorded message instead of contacting a listed number live.
The Federal Trade Commission warns that scammers have called users in the past and falsely offered them an opportunity to sign up for the Do Not Call Registry. It explains that those calls do not come from the Registry or the FTC, and advises users to ignore them and only register their phone numbers via the appropriate section on DoNotCall.gov or by calling 888-382-1222, as of 2015. This way, users can register mobile and home phone numbers free of charge.
Being listed on the Do Not Call Registry blocks sales calls, but it doesn’t prevent telephone surveys, debt collection or political calls. Companies can bypass this restriction in cases where a user gives them a written permission or has recently done business with them. In such cases, a user can submit a request to the company to stop calling him, which that company is legally bound to accept. If illegal robocalls keep coming despite filing a complaint, the only resort for a user is to contact his phone company and file a request to block the offending number.