Make sure the password and username is correct and you are using rawurlencode() for the password field to escape special charatcers in the password.
Please download the custom.zip :
www.softaculous.com/custom/3.8.zip
And use the enduser/installapi.php file class.
----------------------- For immediate support please email us at our Support email address. PMs sent to any Softaculous Team member or posting in the forums is not the official way to get support.
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