4aGoodCause can answer most questions about Authorize.net but there may be times when you need to seek support directly from Authorize.net. 

To get help from Authorize.net use the following resources. 

Call Merchant Support

877-447-3938

Chat with a Merchant Support Representative

Click Live Help from inside your account at https://account.authorize.net

Search the Support Center

Support Center

Training Videos

New Merchant Overview