Refund when order cancelled

I am using a multivendor theme/plugin Dokan, and the TeraWallet.
When the client buys a product, they can choose to pay with the cash on the wallet.
But when the vendor or said client cancells the order, money isn’t refunded onto the client’s wallet?
How does the refund system work with TeraWallet? If an order is cancelled, shouldn’t the money be refunded automatically?

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