Anyone who knows how to resolve this issue on SD config.
Issue: no output created after billing document is saved.
User still needs to trigger manually by going to VF02 >GOTO>HEADER>OUTPUT.
Configuration made for automatic invoice printing for billing document
1. Output Type: ZRD0 u2013 Tharanco Invoice
2. Access Sequence: Z001
3. Output Determination procedure: ZV1000
4. Assign Output type to Partner function
5. Assign Output Det
6. Tcode: VV31, Output Type ZRD0