gtpay payment intergration which giving a hash key error - hash

Question

I have integrated below test php code to integrate gtpay payment in my site.But I am getting following error.
Response Description: Interface Integration Error
It is has key related problem given in the below gtpay integration manual.
https://ibank.gtbank.com/gtpay/IntegrationAPI/mman-tech.html
But I have tried several time to resolve this issue but not getting any solution. Please find the error.
<?php
$the_key = trim('17'.'5664879896'.'200'.'840'.'458742'.'D3D1D05AFE42AD50818167EAC73C109168A0F108F32645C8B59E897FA930DA44F9230910DAC9E20641823799A107A02068F7BC0F4CC41D2952E249552255710F');
$key = hash('sha512',$the_key,false);
?>
<form name="submit2gtpay_form" action="https://ibank.gtbank.com/GTPay/Tranx.aspx" target="_self" method="post">
<!-- <input type="hidden" name="hashkey" value="">-->
<input type="hidden" name="gtpay_mert_id" value="17" />
<input type="hidden" name="gtpay_tranx_id" value="5664879896" />
<input type="hidden" name="gtpay_tranx_amt" value="200" />
<input type="hidden" name="gtpay_tranx_curr" value="840" />
<input type="hidden" name="gtpay_cust_id" value="458742" />
<input type="hidden" name="gtpay_cust_name" value="Test Customer" />
<input type="hidden" name="gtpay_tranx_memo" value="Mobow" />
<input type="hidden" name="gtpay_no_show_gtbank" value="YES" />
<input type="hidden" name="gtpay_echo_data" value="TEST" />
<input type="hidden" name="gtpay_gway_name" value="" />
<input type="hidden" name="gtpay_hash" value="<?php echo trim($key); ?>" />
<input type="hidden" name="gtpay_tranx_noti_url" value="" />
<input type="submit" value="Pay Via GTPay" name="btnSubmit"/>
<input type="hidden" name="gtpay_echo_data" value="">
</form>

Answer 1

You are required to make the hash of [gtpay_mert_id,gtpay_tranx_id,gtpay_tranx_amt,gtpay_tranx_curr,gtpay_cust_id,gtpay_tranx_noti_url,hashkey] (Total 7 params).
You are making the hash key with only 6 params. You missed with the gtpay_tranx_noti_url(gtpay transaction notifying URL).
The gtpay_tranx_noti_url is a required field.

Answer 2

<?php
$the_key = trim('17'.'5664879896'.'200'.'840'.'458742'.'YES'.'D3D1D05AFE42AD50818167EAC73C109168A0F108F32645C8B59E897FA930DA44F9230910DAC9E20641823799A107A02068F7BC0F4CC41D2952E249552255710F');
$key = hash('sha512',$the_key,false);
?>
<form name="submit2gtpay_form" action="https://ibank.gtbank.com/GTPay/Tranx.aspx" target="_self" method="post">
<!-- <input type="hidden" name="hashkey" value="">-->
<input type="hidden" name="gtpay_mert_id" value="17" />
<input type="hidden" name="gtpay_tranx_id" value="5664879899" />
<input type="hidden" name="gtpay_tranx_amt" value="200" />
<input type="hidden" name="gtpay_tranx_curr" value="840" />
<input type="hidden" name="gtpay_cust_id" value="458742" />
<input type="hidden" name="gtpay_cust_name" value="Test Customer" />
<input type="hidden" name="gtpay_tranx_memo" value="Mobow" />
<input type="hidden" name="gtpay_no_show_gtbank" value="YES" />
<input type="hidden" name="gtpay_echo_data" value="TEST" />
<input type="hidden" name="gtpay_gway_name" value="" />
<input type="hidden" name="gtpay_hash" value="<?php echo trim($key); ?>" />
<input type="hidden" name="gtpay_tranx_noti_url" value="" />
<input type="submit" value="Pay Via GTPay" name="btnSubmit"/>
<input type="hidden" name="gtpay_echo_data" value="">
</form>
Its worked if error in gtpay_tranx_id duplicate entry...
Just change any value and reload it.