The assessment was completed under section 143(3) of the Act.  Subsequent to search, reassessment notice u/s 148 was issued. The assessee filed the  return. The assessment was completed by making addition under section 69C of the Act. CIT(A) affirmed the addition. On appeal the assessee contended that order was passed without mentioning of DIN on assessment order hence bad in law. Allowing the appeal the Tribunal held that any communication relating to assessment, appeals, orders, etc. albeit without DIN can have no standing in law having regard to Circular no. 19/2019, dated 14-8-2019. An assessment order and notice of demand are two separate communications qua assessee and carry separate physical existence and identity, even though issued on same date by same Assessing officer pertaining to same assessment year and therefore, necessarily have to carry separate DIN on body of said communications.   Assessment order and notice of demand are two separate communications qua assessee and carry separate physical existence and identity, even though issued on same date by same Assessing Officer pertaining to same assessment year and therefore, necessarily have to carry separate DIN on body of said communications. Where notice under section 148, supply of reasons for initiating proceedings under section 148 to assessee, order disposing off objections, notice under section 143(2), subsequent notices under section 142(1) had been issued electronically due mentioning DIN Number generated through ITBA portal on each of such communication, however, reassessment order had been issued without mentioning DIN on body of said communication, there being partial non-compliance of CBDT Circular No. 27/2019 by Assessing officer while conducting reassessment proceedings electronically,  reassessment order would be invalid and deemed to have been never issued. Order is set aside.  (AY. 2012-13)