(3)Where a company or person proves that it or he has paid the sum due on account of the profession tax levied under this or any other Act for the same half-year to any local authority in the State, such company or person shall not be liable, by reasons merely of change of place of business, exercise of profession, art or calling appointment or residence, to pay to any other local authority more than the difference between such sum and the amount to which it or he is otherwise liable for the profession tax for the half year under this or such other Act.
