PVZGW2 crashing on PS4

I bought PVZGW2 on PS4 for my kids a couple weeks ago. They played in split screen mode for about 3 hrs without issue, then the screen froze and went black. After a minute, the blue PS4 error screen appeared saying "An error has occurred in the following application (CE-34878-0) Plants vs Zombies GW2." The only suggested actions are to run software and app updates which result in the response that the latest versions are already installed. Now every time they try to play, the same thing happens but within a few minutes of starting. This happened even in single player mode and once before beginning any play at all, but now seems to happen only in split screen. If played in single player mode for awhile first and then switched to split screen, it will work for longer but only about 15 minutes. I already replaced the game in case the first was defective and both do the same thing. I also deleted saved data for the game as suggested on another site. My kids love this game and ask me about it every day. Please help!