Question:

When I click add to cart button, I get this {"status":false,"row":null}


Answer:

In this case, it is assumed that's because of conflict between M2 Wholesale Fast Order and M2 Ajax Add to Cart. To solve this issue, could you please try to add layout XML for Wholesale Fast Order page as one of the following screenshots:


Solution 1: 


Solution 2:


Please note that, it's just the solution for your reference.

For more information about product, please refer Wholesale Fast Order for Magento 2 and Ajax Add to Cart for Magento 2 page.
If you need any further assistance, please feel free to contact us.

Please visit our site for more useful Magento 2 Extensions: https://bsscommerce.com/magento-2-extensions.html