The type of activity the seller is taking on the dispute. The allowed value is determined by the current value of DisputeState, returned by GetDispute or GetUserDisputes. Some values are for Unpaid Item disputes and some are for Item Not Received disputes.
See the Field Index to learn which calls use DisputeActivity.
The text of a comment or response being posted to the dispute. Required when DisputeActivity is SellerAddInformation, SellerComment, or SellerPaymentNotReceived; otherwise, optional.
See the Field Index to learn which calls use MessageText.