From FY 2023-24 on words those who opted Old Regime after due date [ 31st July ] automatically converted into New Regime.
Those who opted New Regime after due date late fee of Rs.5,000, which shall be reduced to Rs.1,000 if your total income is below Rs.5 lakh.

Section 80CCD(1) of Income Tax Act

Under Section 80CCD(1) of the Income Tax, an individual can avail for deductions up to Rs 1,50,000 per annum on the total annual income.Payments paid to government-sponsored plans such as the National Pension System, the Atal Pension Yojana, and others.It is a subsection of 80C.

It is applicable only an Old Regime.

Section 80CCD(1) deduction limit is combined with sections 80C and 80CCC.

80C+80CCC+80CCD (1) = Rs. 1,50,000