I did check the address and it says it's there. It says
transactions 2, total received 0.30500001 BTC
Final balance 0.30500001 BTC
Since you have the address, unlock your wallet and dump the private key for that address, then import it into another wallet eg Electrum.
Go to Help, then debug, then console.
Then type:
walletpassphrase "your walletpassphrase here" 600
Press enter then type
dumpprivkey <address that has the balance>
You'll get an alphanumeric string starting with 5, K, or L.
Import that into Electrum to access your bitcoin.