The Voice Authorization phone number is a great resource if your connection with your terminal is down. This phone number allows you to call and obtain an authorization code which will hold the funds on the cardholder's account until you can settle the transaction on the terminal.
If your terminal is down and your Merchant ID begins with 520 you can call 800-991-9911 to collect an authorization code so you can continue to accept credit cards.
Make sure to take down the transaction amount, the credit card number, the expiration date, and the authorization code provided. Keep this information in a locked drawer or box to stay within PCI Compliance.
Once your terminal is back up and running take the authorization code and key in the transaction into the terminal.
For instructions on how to enter in transactions with the authorization code for Dejavoo terminals go here.
For instructions on how to enter in transactions with the authorization code for Verifone Vx520 terminals go here.