You cannot change the type of a return that has already been started. However, you are able to start a new return on your account instead. This will allow you to pick the product type of the new return that you are looking for. To do this follow these steps:
Log into your account.
Click the Tools menu option at the top right of the screen.
Click on the Return Manager option under Tools.
Click the Create a New Return button at the bottom of the popped up window.
You should be presented with a product selector at this point.
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