How to tell them apart?

When processing transactions you might get the same transaction id for an approved/declined/pending/authorized transaction, to tell them apart the status of the transaction is the important part.

The transaction id will not repeat itself within the same transaction status, we recommend when using the getStatus service to use the service by your OrderId which will remove any confusion you may have around transaction ids

Transaction response will include the status code and description along with additional referrences from the provider if Cashier mode is enabled - once you understand the logic it is easier to handle the transaction ids in your system.