This problem arises when Wholesale Now is unable to locate your variant picker on the product page.
If you do not have HTML / CSS experience, please contact support for assistance.
If you do have HTML / CSS experience, feel free to try the steps below:
Visit your product page in the Chrome browser
Right click on your variant picker and select Inspect Element
Copy the variant picker's ID or class name. If you have multiple variant picker dropdowns or swatches on the product page then you will need to choose a class name general enough to apply to all the variant pickers on the page.
In Wholesale Now go to the Settings tab
Scroll down to the Selectors section and paste the class name or ID in to the variant selector field or swatch selector field as appropriate clearing their previous contents
Save your changes
Check your product page to see if the prices in the discount table are changing with the variant changes. If they're not, please contact support for assistance.