Naldson this problem can happen for several reasons, I'll give you some options to see if it solves your problem, come on.
1 ° see if your project is marked as Auto build, eclipse is in Project > BuildAutomatically. If it's not checked, this makes it a little easier.
2 ° When you modify something in your view, is there in the servers tab showing Synchronized? if it is showing republish right click and select the publish option, go to the browser and click F5, see if it worked.
3 ° Try pressing Ctrl + F5 to update, see if it worked.
If not sure, see if the terminal displays some error log.