This problem happens on mobile devices. It is a bit strange, but when you access the site through the URL, the menu works normally, that is, when you click on the 3 horizontal bars, the menu appears. But when I go on google, I do the research and go to the site through google, until the 3 bars of the menu appears but does not open the menu when clicking (touch) the bars. It does nothing and the menu does not appear.
Any idea of the problem? Many thanks.