Had same error on Titanfall 2 (digital copy) for past few weeks everytime I try Multiplayer. This is what I did and it WORKED:
1 - Rebuild database
2 - Start Titanfall 2 (Error in MP)
3 - Delete titanfall 2 game
4 - Restart PS4
5 - Downloaded small app (Youtube)
6 - Rebuild Database
7 - Downloaded Titanfall 2 again and it is working now.