Hello. Me and my team is trying to test the return process via Sandbox environment, but we are stuck at the issue refund process because ebay server keeps telling us there is an error.

url : https://api.sandbox.ebay.com/post-order/v2/return/5000000725/issue_refund payload model: {"comments":{"content":"Here is your refund for return request #5000000721. I have refunded your purchase price,
your original shipping costs, and your return shipping costs."},"refundDetail":{"totalAmount":{"currency":"USD","value":"1.0"},"itemizedRefundDetail":[{"refundFeeType":"PURCHASE_PRICE","refundAmount":{"currency":"USD","value":"1.0"}}]}} result: {"error":[{"errorId":1001,"domain":"returnErrorDomain","severity":"ERROR","category":"APPLICATION","message":"Application encountered an internal error.","parameter":[{"value":"retriable unknown error in OPMS REST - Execute money movement failed.;","name":"message"}],"longMessage":"Application encountered an internal error.","httpStatusCode":500}]}

Is this function not available in Sandbox environment?