A. If a taxpayer fails to make and file any return or report required by the provisions of this Subtitle, the secretary shall determine the tax, penalty, and interest due by estimate or otherwise. Having determined the amount of tax, penalty, and interest due, the secretary shall send by mail a notice to the taxpayer at the address given in the last report filed by him pursuant to the provisions of the Chapter governing the tax involved, or to any address that may be obtainable from any private entity which will provide such address free of charge or from any federal, state, or local government entity, including but not limited to the United States Postal Service or from United States Postal Service certified software, setting out his determination and informing the person of his purpose to assess the amount so determined against him after thirty calendar days from the date of the notice.
B. If a return or report made and filed does not correctly compute the liability of the taxpayer, the secretary shall cause an audit, investigation, or examination, as provided for by R.S. 47:1541, to be made to determine the tax, penalty, and interest due. Having determined the amount of tax, penalty, and interest due, the secretary shall send by mail a notice to the taxpayer at the address given in the last report filed by him pursuant to the provisions of the Chapter governing the tax involved, or to any address that may be obtainable from the U.S. Postal Service or from U.S. Postal Service certified software, setting out his determination and informing the person of his purpose to assess the amount so determined against him after thirty calendar days from the date of the notice.