Every officer, elective or appointive, before entering upon the duties of that office, shall qualify by taking the oath of office prescribed for public officers by the Constitution of the State of Michigan, and by filing the oath with the clerk, together with any bond required by statute, this charter or by the council. In case of failure to comply with the provisions of this section within fourteen (14) days from the date he or she is notified in writing of the officer’s election or appointment, such officer shall be deemed to have declined the office and such office shall thereupon become vacant unless the council shall, by resolution, extend the time in which such officer may qualify as above set forth.