Elements not rendering in 'phone viewport' – TagDiv composer

I have created a new page layout in TagDiv composter which looks great, however when I switch to the ‘phone viewport’ the top 3 modules are missing. Could you help me understand what might be happening here? – http://westisbestwales.co.uk/beaches-aberporth/

Issue found. Just in case someone else manages to make the same mistake as me, I accidentally added the missing modules to the header rather than the page.