If an Alberta patient has given an invalid PHN, or don't know their PHN you can call the Registration Research Unit. If in Edmonton the number is 780.415.2288, outside of Edmonton call 310.0000. They will provide you with a form AHC0406 and request it be faxed in to 780.415.1704.
Note, this only available for in-province Alberta patients. For out of province patients with the incorrect info, you may need to contact the relevant Ministry of Health for more information.