All contracts, granting or giving any original franchise, or extending or renewing or amending any existing franchise, shall be made by ordinance and not otherwise. Every such ordinance granting a franchise shall be accepted in writing by the grantee before said ordinance takes effect, and if it is to be submitted to the electors, it shall be so accepted before its submission. Such acceptance shall be filed with the clerk. Any noncompliance with this section shall automatically annul such franchise.