TDS interest

1.5% Interest  to be calculated from the date of deduction ( calculate including date of deduction month ) 
for e.g.  date of deduction is 10/07/2019 and date of payment of tds is 10/08/2019 (i.e. late by 3 days)
then interest will be calculated for two month i.e. July and August 2019.

1000 x 1.5% Interest = Rs. 15 multiply by Two Months i.e. Rs. 30.