veronika,
Thank you for taking the time to send us the reports. We have identified the issue and it should be a quick fix.
Please open the WooCommerce Settings and click the Products tab. Once there, click the Display sub-menu item and update the Shop page to the proper page used by your site.
If you have any trouble with this, please let us know.
Also, if you feel that our plugin is useful, we ask that you take a moment to give us a 5 star review here: https://wordpress.org/support/view/plugin-reviews/wp-facebook-pixel#postform. If you do not feel we deserve 5 stars yet, please let us know what we can do to earn all 5 stars before submitting a review.
Best wishes,
Jacob