Claimed errors in the calculation of assessments shall be called to the attention of the finance officer, who shall determine whether there has been an error in fact. If the finance officer shall find that there has been an error in fact, he or she shall recommend to the council an amendment to the assessment ordinance to correct the error. Upon enactment of the amendment, the finance officer shall make the necessary correction in the docket of city liens and send a correct notice of assessment by certified mail.