That’s completely normal. Our database servers are not connected to the public internet, they are only accessible from within network.
If you’re trying to access the database from our hosting, please explain the actual issue you’re experiencing. Trying to ping the database servers from your own computer will not give you any information to help solve whatever issue you’re experiencing.
If you’re trying to access the database from anywhere else, note that this is not possible on free hosting, it’s a premium only feature.