It sounds like the .nCopyLinesFromSalesOrder(soOrder) method is duplicating lines when you import them from the Sales Order into the Shipping Invoice in your system. This could be due to a few reasons, such as issues with how the method is called or a potential bug in the script.

Here are a few steps you can take to troubleshoot and resolve this issue:

1. Check How the Method is Called: Make sure that the method .nCopyLinesFromSalesOrder(soOrder) isn't being called more than once in your script or workflow inadvertently.

2. Review the Method's Configuration: Sometimes, methods like these can have configuration settings or parameters that determine how they operate. Ensure there are no settings that might cause line duplication.

3. Examine Event Triggers: If this method is triggered by an event (like a button press or a field update), ensure the event is not firing multiple times. For example, a button might be clicked twice, or a field update might be triggering the method unexpectedly.

4. Look for Loops: If the method call is inside a loop, make sure the conditions governing the loop are correct and not resulting in repeated method calls for the same order.

5. Check for Software Bugs: There might be a bug in the software you are using. Review the software's documentation or support forums for any known issues. Contacting support with a detailed description of your issue might also uncover a solution.

6. Log and Debug: Add logging before and after the method call to see exactly when it's called. This might help you identify unwanted multiple executions.

It sounds like the .nCopyLinesFromSalesOrder(soOrder) method is duplicating lines when you import them from the Sales Order into the Shipping Invoice in your system. This could be due to a few reasons, such as issues with how the method is called or a potential bug in the script.

Here are a few steps you can take to troubleshoot and resolve this issue:

1. Check How the Method is Called: Make sure that the method .nCopyLinesFromSalesOrder(soOrder) isn't being called more than once in your script or workflow inadvertently.

2. Review the Method's Configuration: Sometimes, methods like these can have configuration settings or parameters that determine how they operate. Ensure there are no settings that might cause line duplication.

3. Examine Event Triggers: If this method is triggered by an event (like a button press or a field update), ensure the event is not firing multiple times. For example, a button might be clicked twice, or a field update might be triggering the method unexpectedly.

4. Look for Loops: If the method call is inside a loop, make sure the conditions governing the loop are correct and not resulting in repeated method calls for the same order.

5. Check for Software Bugs: There might be a bug in the software you are using. Review the software's documentation or support forums for any known issues. Contacting support with a detailed description of your issue might also uncover a solution.

6. Log and Debug: Add logging before and after the method call to see exactly when it's called. This might help you identify unwanted multiple executions.