Dawn 15.0.2 - PageSpeed Insights 'Touch targets do not have sufficient size or spacing'

[DameandtheDevil]

Hi, while doing a speed check on PSI, there is an issue with 'Accessibility'...  'Touch targets do not have sufficient size or spacing'. It provides a solution. I have attempted to locate where I need to add the solution, without success. Can someone please point me in the general direction? I am using Dawn 15.0.2.