" GTM no-script code not found: possibly lacking or not in " I try so as to add the script inside the header.tpl but there is no area. Update: Problem was solved. I just use another addon and customize hook to make it happen. Many thanks Ali Edited November 21, https://addons.prestashop.com/pl/seo-pozycjonowanie-naturalne/30904-automatyczne-tagi-hreflang-i-tagi-kanoniczne-seo.html