tax on cash sale Rs.20000

if a co. made  a sale for Rs. 22000/-and has been asked to get the tax deducted on payment but we dont want to get the tax deducted therefore we assume that on the time of payment the cash falls short by Rs. 4000/-we received 18000/- on spot and balance on delivery next day.even then the tax will be deducted if yes under which section.

Thanks & Regards

Abid

Accountant