Header.php is empty in Generatepress

I tried to add Google Analytics in header.php file as requested but now,everything is missing in that file. It’s empty and the main page does not work with Generatepress any more. I thought it could be an Elementor issue so I tried to use a different theme and works well with them. What can I do to get back? I would like to keep using GeneratePress Theme. Please, help me. Thank you.

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