Hello Amar,

Thank you for your response regarding integration. I am happy to assist!
Issues with these values or with the generation process can cause Error 99. The most likely causes of Error 99 are:

-The Transaction Key that you have embedded in your script may not be correct.

Generate a new Transaction Key, disable the old Transaction Key, enter the new value in your script and test the connection.

To obtain the Transaction Key:
1.Log into your Merchant Interface.
2.Click Account from the main toolbar.
3.Click Settings in the main left-side menu.
4.Click API Credentials & Keys.
5.Enter your Secret Answer (the answer to your Secret Question configured at account setup).
6.Select New Transaction Key.
7.To disable the old Transaction Key, click the check box labeled Disable Old Transaction Key Immediately.
(NOTE: If the Disable Old Transaction Key Immediately check box is not selected, the old transaction key will automatically expire in 24 hours.)
8.Click Submit to continue. Your new Transaction Key is displayed.

Please be sure to have your API Login ID and Transaction Key set in your scripts. If you are using our SIM sample code in PHP, these fields must be filled out in your simdata.php file. In the PERL sample script, it must be entered into the sim.pl script. Sample scripts are available at Sample Code page on Github.

-You may not be properly posting all the required fields for SIM or DPM.

The following fields must be present in your payment form request in order for the transaction to be accepted:
•API Login ID (x_login)
•The sequence number of the transaction (x_fp_sequence)
•The UTC time, expressed in seconds (x_fp_timestamp)
•The amount of the transaction (x_amount)
•The Fingerprint Hash (x_fp_hash) generated from the Transaction Key and the four above fields.

-If you are attempting to pass the field x_currency_code with your payment form request, you must include this field in your fingerprint hash generation.

When you generate the fingerprint script, you must use the Transaction Key to hash an input string of the following fields, in this exact order, delimited by the caret (^) character:
1.x_login
2.x_fp_sequence
3.x_fp_timestamp
4.x_amount
5.x_currency_code (optional)

-If you use x_currency_code then the input string would resemble this example:

APIl0gin1D^Sequence123^1457632735^19.99^USD

Alternately, you may stop passing x_currency_code and use your account's default currency. In this case you would drop the currency code from the input string, but not the caret before it:

APIl0gin1D^Sequence123^1457632735^19.99^

 
For more information, see our Error 99 resolution tool:
https://developer.authorize.net/api/reference/responseCode99.html

I hope this information helps.

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Mary P.
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