Hi, the number one reason would be that your pages are not linked to the ectcart.js file. Details in this thread - https://www.ecommercetemplates.com/support/topic.asp?TOPIC_ID=107040
If that's not the case, be sure to post back with more specific details of the issue.
I think the number 2 reason is that the location you set to the ectcart.js script is incorrect. If that doesn't help that can you let us know the URL of the site so we can see what is happening.
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