Can't get Ship via combo to reflect change

I am able to update the Shiphead dataview. I can’t get the change to reflect the shipviacode change. I have sent the description into shipviadescription. I have tried selected text on the combobox and a few other properties I thought might work. What I don’t understand is the change does not reflect until I close out of customer shipment and come back in. I am using a list view for the user to select a carrier from a list that has other information for the user to decide the best shipper. Any Ideas would be greatly appreciated.

edit: This is for C# classic customization

The best bet here is to try to identify the method that epicor uses to do the same action. Turn on tracing, perform the action that changes the shipvia using the standard epicor tools. This records the methods that epicor is using. Then use Jose’s trace parser Trace Helper Utility for Epicor ERP 10 - ERP 10 - Epicor User Help Forum (epiusers.help) to see which methods are firing. Once you identify the method, you can also use the trace parser to see which field need to be populated. There could be a few steps epicor takes other than just updating the text value of the field.
Good Luck!