Why is the invoice generation error coming up in the e-way bill and not in the invoice directly? How are these two linked?

To generate the e-way bill and E-invoice without errors, follow these steps:
 Step 1: Open BUSY.
 Step 2: Go to Administration.
 Step 3: Click on Configuration.
 Step 4: Select 'Feature and Options.'
 Step 5: Choose GST/VAT.
 Step 6: Enable E-Invoice & E-way Bill and provide the 'Place' and 'Pincode.'
 Step 7: Fill in all the details for E-Invoice & E-way Bill Configuration.
 Step 8: Click on GSP Configuration.
 Step 9: Enter Webtel and Pinnacle ID's.
 Step 10: Open the E-Invoice & E-way Bill Portal and click on the 'Registration' option to enable e-invoicing.
 Step 11: Access the e-Waybill portal on the left side using your existing credentials.
 Step 12: Register for GSP.
 Step 13: Authenticate yourself with an OTP.
 Step 14: Add a new user.
 Step 15: Select GSP Name as 'Webtel Electrosoft Pvt Ltd' or 'Pinnacle Finserv Advisors Private Limited.'
 Step 16: Enter the appropriate Username and Password and add the user.
 Step 17: Enter the same username with the prefix and password in the credentials table under GST Settings in BUSY.
 Step 18: Go to Voucher Series Configuration and select the voucher type.
 Step 19: Choose the Voucher Series in which you want to use E-Invoice & E-way Bill.
 Step 20: Enable the Transport window on the top right side.
 Step 21: Enable the E-Invoice & E-way Bill option on the bottom right side.
 To register for E-invoicing with your GST number, log in to the E-invoice Portal and enable registration for E-invoicing.
 Step 22: Now, when you add a voucher and save it, a window will prompt, asking if you want to generate an E-Invoice. Click on it.
 Step 23: Fill in the transport window accordingly.
 Step 24: Select 'Automatic,' check for errors, and resolve them as needed.
 Step 25: Press F2 to save this window and generate the E-way bill.
 Step 26: You can directly print the E-Invoice & E-way Bill from BUSY, and there is no time limit for printing.