Bug while saving a doc

I have a Salary Slip doctype which have two child tables of Salary Detail. When I delete a record of Salary Detail Table and save the salary slip doc, The component is never deleted and comes back on saving the draft Salary Slip.

Normal update works fine, like updating the non table fields of Salary Slip.

Hi you have mentioned that you have 2 child tables of Salary Detail, 1 is for Earnings and 1 is for Deductions?