I'm using the theme -
I purchased the theme from themeforest and had the application set up on a hosting. I'm using Magento ver. 2.1.1. After adding products into the shopping cart, when I clicked checkout, it threw an exception:
Cannot instantiate interface Magento\Vault\Api\Data\PaymentTokenInterfaceFactory in /home/shopegiv/public_html/dev/vendor/magento/framework/ObjectManager/Factory/Dynamic/Developer.php on line 73
I tried to resolve the same by putting this line in app/etc/di.xml:
< preference for="Magento\Vault\Api\Data\PaymentTokenInterfaceFactory" type="Magento\Framework\ObjectManager\Factory\Dynamic\Developer" />
Thereafter, the fatal error went away, but now I get the following error in var/log/system.log:
Argument 15 passed to Magento\Paypal\Model\Payflow\Transparent::__construct() must implement interface Magento\Vault\Api\Data\PaymentTokenInterfaceIFactory,
instance of Magento\Framework\ObjectManager\Factory\Dynamic\Developer given, called in /home/shopegiv/public_html/dev/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php
on line 93 and defined in /home/shopegiv/public_html/dev/vendor/magento/module-paypal/Model/Payflow/Transparent.php on line 99  
The output displayed on the screen was Object DOMDocument should be created.
I assume I'm not going the right direction to specify the preference or specify concrete factory such as
If someone could advice the workarounds split into steps, I shall be thankful.
I would greatly appreciate any help on this.