Hide native menu in MOBILE page

Hi,

I have installed this plugin and am very happy with it. However, I cannot hide my theme menu. I have hidden part of it and now only the 3 horizontal lines from my theme menu is noticeable so I just wanted to know whether there is a way to get rid of the 3 horizontal lines from the theme menu since it is so confusing on the mobile page to have 2 sets of horizontal lines?

Thank you!

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