Some Discount Ninja require that your currency format contains a "money" css class.
If you need to update your Shopify settings, follow these steps:
Locating your Shopify currency settings
To change your currency settings in Shopify, go to Settings > General and click "Change formatting" in the "Standards and formats" section:
Changing base currency
Select a new base currency from the list if required:
Changing your Shopify currency formatting
Click the link "Change formatting":
Shopify will then allow you to modify your settings:
Update the first two rows:
HTML with currency
HTML without currency
You'll want to add the following before the text:
<span class="money">
And the following after the text:
</span>
So, the above example becomes: