Answer:
- Go to Main Menu > Sales Management > Transaction > Sales Invoice (POS) (S > T > S)
- Alt + O (open option screen)
- In Mode Of Payment field press Enter
- Delete all MOPs
- Alt + L(Open list)
- Select Credit Sale first, then select Cash and other MOPs
- Press Enter
- 8. Save
- Now, whenever you want to tender a credit sale (after selecting the customer) default MOP will be Credit Sale.

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