Held that the AO having disallowed part claim of deduction under s. 57 after making a detailed enquiry and satisfying himself that the assessee is eligible to claim deduction under s. 57 in respect of the remaining amount as claimed by the assessee, the assessment order cannot be said to be erroneous insofar as prejudicial to the interests of the Revenue. Order passed by the Principal CIT under s. 263 is quashed. (AY. 2018-19)