Chartered Accountant
2414 Points
Joined November 2016
Section 31(1) says-
A registered person supplying taxable goods shall, before or at the time of,—
(a) removal of goods for supply to the recipient, where the supply involves movement of goods; or
(b) delivery of goods or making available thereof to the recipient, in any other case,
issue a tax invoice showing the descripttion, quantity and value of goods, the tax charged thereon and such other particulars as may be prescribed:
Thus you have to issue invoice at the time or before the removal of goods. What you are doing is incorrect as per law.