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


To solve this issue, could you please try to add layout XML for Wholesale Fast Order page as one of the following solution:

<referenceContainer name="before.body.end">
<referenceBlock name="bss.ajaxcart" remove="true" />


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.

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