Logo not appearing on Mobile

Hi there,

Unfortunately I am travelling on a break, and my graphic designer has a bit of an issue with a site she is working on, that is being redeveloped from it's original version.
(link below).
I've summarized as best I can - hope this makes sense, and sorry for a bit of vagueness about the issue!
Dave
ps - Had a browse for other similar issues here, but nothing that gives me any solution.

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Logo is added to all possible places.
1. If I turn Mobile Header Off I get a large top gap with just the hamburger and the word Menu, and no logo.
2. If I turn mobile header ON, I see the logo in the customizer, but not on my phone.
- Also if I make FireFox mobile size I see the logo, it only seems to be on a phone that the main issue of the logo not appearing is happening.
3. I uploaded a test SVG logo, and it displays in the customizer preview but not on my phone.
(I have been clearing the cache - )
4. I removed some custom CSS, it made no difference to anything - may have been from previous version of the site.
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