Add to CArt Button Appears and Dissappears

Hi, I added Zippay widget to my site, I’m having problems with my “add to cart” button. when I click on an item to add to the cart button appears for 1 second when the page loads and then dissappear immediately, I’m unable to add any product to the cart, because the button is simply not there. This only started happening after I added the ZipPay plugin. Has anyone else had this problem?

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