Uncaught TypeError: btn is null

Hello
I am always getting the error in my console:

Uncaught TypeError: btn is null

<anonymous> https://shop-eu.biomed-int.ch/wp-content/plugins/remove-add-to-cart-button-for-woocommerce-premium/public/js/remove-add-to-cart-button-woocommerce-public.js?ver=1.0.9:44

????jQuery 2

remove-add-to-cart-button-woocommerce-public.js:44:3

????<anonym> https://shop-eu.biomed-int.ch/wp-content/plugins/remove-add-to-cart-button-for-woocommerce-premium/public/js/remove-add-to-cart-button-woocommerce-public.js?ver=1.0.9:44

????jQuery 2

As I am not a very develope coder I am not able to get rid of the error. But it has to do something with the remove add to cart button.
Can you help me fixing the issue?

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