To check if any vouchers are non-taxable, you need to follow the below steps:
Step 1: Go to Display, then select Account Books.
Step 2: then select Account Registers (standard), then select Sales Register or which report you want to check, then select date range and relevant information, then select all sales types.
Step 3: then select All parties, then select the sales registered date range for which you want to check the non-taxable.
Step 4: In that, you will find the option to show bifurcation of amounts. Set yes to this option.
Step 5: and then press F2 or OK to load the report; it will show the bifurcated tax amount, in that you can see the GST amount bifurcation in that you will the taxable value and not-taxable value.