This error indicates that the OfferCreate transaction failed because the account creating the offer does not have any of the offered currency.
Things you can do:
- Check the available amount of currency you want to sell. Check your reserved amounts if selling XRP.
- Change the trading pair.
- Check if you actually want to sell the currency in question. If you actually want to buy the currency switch the direction of the order above the trade amounts form.
- Deposit more of the currency you wish to sell.