The Mayor of the District of Columbia is hereby authorized and instructed to cause all taxes erroneously paid in the District of Columbia to be refunded by the proper accounting and disbursing officers of said District, upon the certificate of the Collector of such erroneous payment, which certificate shall state the nature of the error, the name of the person or persons by whom such excessive payment was made, and such other particulars as may be necessary to satisfy the accounting officers that such claim for reimbursement is just and equitable; and the said accounting and disbursing officers shall pay all moneys so refunded out of, and charge the same to, the fund which was credited with the erroneous payment. “Taxes” as discussed herein do not include the “special franchise tax” as provided for in § 34-912.