Domain name registrants or owners are supposed to provide accurate and correct registration information, such as address, telephone number and e-mail address. However, registrants often enter false mailing address and telephone number information because it increases the difficulty of finding the domain name registrant. Fortunately, domain name registrars will help you correct any inaccurate registrant information.
Domain name registrars require as part of their registration agreements that registrants provide current and accurate. For example, GoDaddy's Domain Name Registration Agreement at Section 4 (emphasis added)
You [the registrant] agree to notify Go Daddy within five (5) business days when any of the information you provided as part of the application and/or registration process changes. It is your responsibility to keep this information in a current and accurate status. Failure by you, for whatever reason, to provide Go Daddy with accurate and reliable information on an initial and continual basis, shall be considered to be a material breach of this Agreement and a basis for suspension and/or cancellation of the domain name.
The initial and continuing requirement exists because domain name registrars must maintain a public database -- the WHOIS database -- that "is available to be searched by the members of the public in order to allow rapid resolution of technical problems and to permit enforcement of consumer protection, trademark, and other laws." See Whois Data Reminder Policy (WDRP) FAQs For Domain Name Registrants, at "What is a Whois Record? What is my duty to keep the information in the record current?"
Thus, when a domain name registrar is informed that a registrant has entered false information, they will attempt to contact the registrant to obtain corrected inaccurate information. If the registrar can reach the registrant, then the information will be updated and you will have an accurate contact information for the registrant. If the registrar cannot reach the registrant, then the registrar will suspend or cancel the domain name until the registrant contacts the registrar and updates its contact information.