No improvement assessment shall be invalid by reason of a failure to give, in any report pertaining to the proposed public improvement or the proposed assessment or by reason of a failure to insert in the assessment ordinance or ordinance or in the lien docket or elsewhere in the proceedings, the name of the owner of any lot, tract or parcel of land or part thereof, or the name of any person having a lien upon or interest in the property, or by reason of any error, mistake, delay, omission, irregularity or other act, jurisdictional or otherwise, in any of the proceedings or steps hereinabove specified, unless it appears that the assessment as made insofar as it affects the person complaining, is unfair and unjust; and in that event the Council shall have power and authority to remedy and correct all these matters by suitable action and proceedings.