Why do I need to accept ₹5,000 or ₹15,000 limit for setting up a UPI AutoPay?

Important: On accepting a limit of ₹5,000 or ₹15,000 no money will be deducted from your account. A minimum amount of ₹1 will be deducted to set-up the mandate, which will be refunded to your account later. 

You need to set-up a limit of ₹5,000 or ₹15,000 depending upon the bank with whom you have your settlement account. The bank sets a maximum limit upto which a lending partner can deduct money from your bank account if you fail to pay them.
Note: This is the maximum amount that the lending partner can deduct from your bank account to recover your overdue or missed installments.