If you want to buy Ripple on Bitit make sure that you've specified the correct Destination Tag while adding your wallet address.
A Destination Tag is required to identify your transaction when sending to a Ripple wallet or an exchange.
For instance, exchanges like Kraken ask the users to include a Destination Tag when the user makes a deposit to the exchange. In this case the Destination Tag identifies the user within the receiving exchange.
The exchange or wallet will provide you the Destination Tag. You will just need to enter it in the "Destination Tag" field on Bitit in addition to your Ripple address.
However some exchanges don't require the Destination Tag, so you’ll only need to add your Ripple address on Bitit.
Please make sure that you have a Destination Tag, if required.
If your Ripple wallet requires a Destination Tag and you make a mistake or forget to add the Destination Tag, your funds may be lost. Please contact the exchange/wallet where you sent the funds in order to retrieve your funds; they then should be able to credit your account.