Have you tried all of these:

-Make sure you have some HDD space

-Check the game trophies, are they installed or not

-Allow BD mirror

-Compare the Backup size with the Original disc size

-Go to recovery mode & rebuild data base, How?
1- turn off your PS3, then turn it on & keep holding the power button until it shuts down
2- then turn it on & keep holding on the power button you'll hear one beep
keep holding until you hear two consequent beeps, take off your finger.

Then choose Rebuild Database, don't worry it won't delete anything.
Now play the game & see what will happen then inform us.

Have a nice day.