You just bailed and you got your shirt dirty!

All you need to do is find a section of water and continously go into it. You'll see after a while that your shirt will get cleaner. It may still have a faded dirt mark in it. Unless you want to make it 100% spend a few mins diving into the water (tt took me around 10 mins to get my White dress shirt 100% clean!).

Also, you can go into edit skater and change a small thing like: add jewllery, change skateboard etc. Either way, your shirt will be clean!