Tax deductions on low salary

I got the latest payslip and could see tax deducted by 1300+, I went to the tax statement for the year in Ux, the cumulative salary which is on March is 3lakh+ only after all deduction, and could see the tax is calculated on the range of 3-6 lakhs category, I was choosen new regime, somebody know why it's deducted the amount from the salary as the new regime limit was 7 lakhs after all deduction?