The assessment order bore only a manually written DIN, while the computer-generated DIN was issued nearly three weeks later. The Tribunal held that CBDT Circular No. 19/2019 mandates that every communication must bear a computer-generated DIN at the time of issuance. Subsequent generations of DIN cannot cure the defect. Accordingly, the reassessment proceedings were held to be void ab initio. (AY. 2014-15 to 2017-18, 2019-20 to 2022-23)