What are the modes of recovery of tax available to the proper officer

The following options are available to the proper officer:
(a) The proper officer may deduct or may require any other specified officer in Form GST DRC-09 to deduct the amount so payable from any money owing to such person – Refund adjustment.
(b) The proper officer may recover or may require any other specified officer to recover the amount so payable by detaining and selling any goods belonging to such person –Detaining and selling of goods.                                        (c) The proper officer may, by a notice in Form GST DRC-13, require any other
person from whom money is due or may become due to such person or who
holds or may subsequently hold money for or on account of such person, to pay to the credit of the Central or a State Government – Recovery from third parties.
(d) The proper officer may, on an authorization by the competent authority, distrain any movable or immovable property belonging to or under the control of such person, and detain the same until the amount payable is paid; if the due remains unpaid for a period of thirty days after any such distress, he may cause the said property to be sold and with the proceeds of such sale, may satisfy the amount payable and the costs including cost of sale remaining unpaid and pay the surplus amount, if any, to such person – Detaining / attachment of movable or immovable property and adjustment of tax dues from sale proceeds.
(e) The proper officer may prepare a certificate signed by him specifying the amount due from such person and send it to the Collector of the district in which such person owns any property or resides or carries on his business and on receipt of such certificate, the Collector shall proceed to recover from such person the amount specified as if it were an arrear of land revenue – Recovery of tax dues as arrears of land revenue.

(ICAI FAQ PUBLICATIONS 06-09-2017 Recovery of tax: FAQ NO. 43)

Whether a taxable person who has paid CGST and SGST or, as the case may be, CGST and UTGST on a transaction considered by him to be an intra-state supply, but which is subsequently held to be an inter-state supply is required to pay interest

No. A registered person shall not be required to pay any interest on the amount of IGST payable.

(ICAI FAQ PUBLICATIONS 06-09-2017 Tax wrongfully collected and paid to Central Government or State Government: FAQ NO. 39)

Whether a registered person who has paid IGST on a transaction considered by him to be an inter-state supply, but which is subsequently held to be an intra-state supply is required to pay interest

No. Such registered person shall not be required to pay any interest on the amount of CGST and SGST or CGST and UTGST payable, as the case may be.

(ICAI FAQ PUBLICATIONS 06-09-2017 Tax wrongfully collected and paid to Central Government or State Government : FAQ NO. 38)

What happens if a registered person has paid CGST and SGST or, as the case may be, CGST and UTGST on a transaction considered by him to be an intra-state supply but which is subsequently held to be an inter-state supply

Refund of CGST and SGST or, as the case may be, CGST and UTGST shall be granted in such manner and subject to such conditions as may be prescribed.

(ICAI FAQ PUBLICATIONS 06-09-2017 Tax wrongfully collected and paid to Central Government or State Government : FAQ NO. 36)