Unable to claim chapter vi a deduction in ITR 3 of individual

I have paid Rs.207292 as LIC of which Rs.150000 is eligible for chapter vi a deductions. But when I fill in the details of the deductions in the relevant schedule the amount of deduction is shown as zero instead of Rs.150000. Please help as I am facing this issue for almost 5 days now. I have refilled the form twice but getting the same error.