You don't have sufficient cash in your eWallet, which means you cannot copy/duplicate new trades (to open) from your Master(s) to the Slave that is using a Prepay plan. However, the closing of trades is always possible. If you need to continue to copy/duplicate trades, please deposit cash in your eWallet by going in your Cockpit -> Your eWallet -> "Recharge your eWallet"

Learn more on your "eWallet".