Nav drop down menu behaving strangely in device view mode

Hi all,

I’m not sure why, but when I go to preview the drop down menu in my nav bar in device views. The font changes from the brand font (Poppins) to a serif font. The colours still behave as they should and change when on hover but the font is not sticking to what it should be. I have dropped a couple of screenshots in to show this.

If anyone can point me in the right direction to help me fix this that would be great.

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