Your balance before you have deposited via Liberty Reserve was less than 7.57 USD. It mean your WMZ balance was less than 7.57 USD.

Then you have depsoited via Liberty Reserve 5 USD and ordered withdraw on 7.57 to Webmoney. You should order withdraw on 5 USD to Liberty Reserve and 2.57 to Webmoney only.

Please do not use trading account as exchange point between different e-payment sytems. You can use account for trading on Forex only, not for exchange money from one e-payment system to other. And a sum of your operation does not matter: financial department can not allow exchange from Liberty Reserve 5 USD as 50000 USD.

Follow simple anti-exchange rules and you will never have any refunds of money to trading account. What you can do now I have written above: you should just order withdraw to Liberty Reserve on 5 USD and withdraw to Webmoney to 2.57 USD.

Do not search problems where they have not place.

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Sincerely yours, official representative of InstaForex
www.instaforex.com