A transaction status is a state that your transaction is currently in. While making a payment, you will progress through different states of a transaction, each with its own meaning. For example, an "accepted" status transaction is one that has not been paid, but one that you've agreed on paying for the next time you top up your account.
The following is a chart of the states of a transaction. Transactions such as these are limited by volume daily.
Here's a list of Xfers transaction status and their respective meaning.