There are 2 options to submit complaint:

1. Message directly via platform chat service.

2. Click [Complain] to platform customer service to lodge a complaint.

Click [Yes] to confirm you want to dispute. The Trade.

To check on the DISPUTE trades history, please follow the below steps:

1) Click 【OTC Order】

2) Select [Dispute Trades]

3) The DISPUTE trade will be reflected as below screenshot.

There are 2 options for seller to cancel complaint on dispute reported.
1) You may click [Cancel Complain] upon receiving the payment from buyer.

2) Wait patiently for the reply from customer service team.