Section 80CCD(1B) clearly states that irrespective of any deduction allowed in sub section 1 an assessee can claim deduction of upto 50000 under sub section (1B) so I guess you can easily claim additional deduction of 50000 under sub section 1B. If your account office doesn't give you claim you yourself can claim it while filing return of income I don't think there will be an issue.
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