1. Every person making any taxable sales of property or service, except transactions provided for in sections 144.070 and 144.440, individually or by duly authorized officer or agent, shall make and file a written return with the director of revenue in such manner as he may prescribe.

2. The returns shall be on blanks designed and furnished by the director of the department of revenue and shall be filed at the times provided in sections 144.080 and 144.090. The returns shall show the amount of gross receipts from sales of taxable property and services by the person and the amount of tax due thereon by that person during and for the period covered by the return. With each return, the person shall remit to the director of revenue the full amount of the tax due.

3. In case of charge and time sales the gross receipts thereof shall be included as sales in the returns as and when payments are received by the person, without any deduction therefrom whatsoever.

4. If an error or omission is discovered in a return or a change be necessary to show the true facts, the error may be corrected, the omission supplied, or the change made in the return next filed with the director for the filing period immediately following the filing period in which the error was made or the omission occurred, as prescribed by law, except that no refund under this chapter shall be allowed for any amount of tax paid by a seller which is based upon charges incident to credit card discounts. Any other omission or error must be corrected by filing an amended return for the erroneously reported period if the amount of tax is less than that originally reported, or an additional return if the amount of tax is greater than that originally reported. An additional return shall be deemed filed on the date the envelope in which it is mailed is postmarked or the date it^* is received by the director, whichever is earlier. Any payment of tax, interest, penalty or additions to tax shall be deemed filed on the date the envelope containing the payment is postmarked or the date the payment is received by the director, whichever is earlier. If a refund or credit results from the filing of an amended return, no refund or credit shall be allowed unless an application for refund or credit is properly completed and submitted to the director pursuant to section 144.190.

5. The amount of gross receipts from sales and the amount of tax due returned by the person, as well as all matters contained in the return, is subject to review and revision in the manner herein provided for the correction of the returns.