I'm using the Mystile theme for WooCommerce and this is the error message I get when I click on the checkout page:
Warning: Cannot modify header information - headers already sent by (output started at ***siteaddress***\wp-content\themes\mystile\includes\theme-woocommerce.php:1) in ***siteaddress***\wp-includes\pluggable.php on line 896
What could be the problem?
Here's my theme-woocommerce.php code (with some titles translated):
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