Don't worry - the following procedure will not delete your game save data. Clear your console's cache by doing the following steps:
1. Turn off the PlayStation 4 by pressing the power button on the front panel. The power indicator will blink for a few moments before turning it off.
2. Once the PlayStation 4 is off, press and hold the power button. Release it after you have heard two beeps: one when you initially press it, and another one 7 seconds later.
3. Connect the DualShock 4 controller with the provided USB cable and press the PS button on the controller.
4. Choose "Rebuild Database".
Additionally, make sure the game's been correctly installed with all of its updates.