woocommerce snippet ajax mini cart not working

I used this snippet https://docs.woocommerce.com/document/show-cart-contents-total/, but when I deleted it, cant add products to cart anymore – just endless loading animation and shop cart empty. And layout also broken, in body tag now all meta, link tags and at the top of all pages letter “d”. I read something about fragment cache, but I dont know how to fix this.