Discount in eway bill

no need for showing the discount as a separate  item. Put the value which is coming after discount at the taxable value column.

Or you may input your Total Discount price in the 'Other Amount(+/-)" box.

But you have to calculate the Tax separately and the input must contain the Total Discount price inclusive of Tax

For Example: Discount Price : 20000 and GST : 18%  

= 20,000 + 20,000*18%

= 20,000 + 3,600(Tax)

= 23,600

So, 23,600 INR will be the Total Discount Price Inclusive of Tax.

Correction: Discount Amount