I send request to https://api.bitforex.com/api/v1/trade/placeMultiOrder and I receive "message" => "SignData Invalid”.
request example: https://api.bitforex.com/api/v1/trade/placeMultiOrder/api/v1/trade/placeMultiOrder?accessKey=28eb7ae2dbe5ee6c4c64355b98d9e103&nonce=1548761658230&ordersData=%5B%7B1%7D%5D&symbol=coin-usdt-btc&signData=c65fc158ea28c884ceb57abb37319da296ab61abd2e58bed11fa5be2a3c664c1

I think the problem in ordersData param, could you please give me example of work request?