There should be a push clip that holds it from the wheel well area. Check the other side to see which clip is needed. This may help hold it in place.
This is an awesome link. Good info here.3m has some repair info for bumpers, plastic, tabs etc...
https://www.3m.com/3M/en_US/collision-repair-us/applications/bumper-and-plastic-repair/#
I have a lot of trust in 3m products. So far, every 3m product I've used has been excellent.