Crashing

The last three games I purchased have either not opened and when they do you might be lucky to get to end of trial, then it asks you to download, you tap already purchased, nothing happens, you tap download, insert your iTunes password, then then you get a screen advising you have already purchased and would you like it again for free, I choose this option, then the games either stall at that screen or crashes to main menu, have tried numerous times and same thing over and over. Not happy.