Hello,
We can’t check your site using real device because we get error http://prntscr.com/t1g9y4 We are located in Europe and it looks that you don’t allow access to your site for Europe.
If we use VPN and Chorome emulation we don’t see the issue https://gyazo.com/474ad0237f554740f44fbfa158908318
Could you, please, send us a video of your problem with the mobile menu?
Regards