[misc] do people actually reapply sunscreen every 2 hours?

Beauty Tips For Body Care
I know that you're supposed to reapply sunscreen according to the direction but I've never actually done it before. I usually just put facial sunscreen on in the morning and that's it? Would this actually harm me in the long run. Should i start reapply the sunscreen?If i want to reapply, do i clean my face completely before reapplying?
Girls Blog 2015
Submitted by 1smallercap