Welcome to the Forum! Best way to get that answer is to use the "Search" engine on this page. Enter "spots on TPO Roof" and then read for an answer.
The cleaning product I use for about everything is Simple Green. Roof, sides, carpet, inside fridge, anything. Works well diluted and for trouble spots I use it full strength.
Hope you find the answer. LB
Retired January 4th, 2018 Lynne & Jerry RVM 105
04 WBGO Itasca Sunova (Miss May) Blue Ox Tow Bar
15 Equinox (Noxi) 18 RAD Mini e-bike, 04 Tracker