Header error log

Warning: Cannot modify header information – headers already sent by (output started at /home/wp_fyrkyv/sonofabarista.com/wp-content/plugins/per-product-addon-for-woocommerce-shipping-pro/plugin-update-checker/Puc/v4p4/Plugin/UpdateChecker.php:641) in /home/wp_fyrkyv/sonofabarista.com/wp-includes/functions.php on line 6712

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