Error reading steam P2P#1910

Hello, my friends and I have a problem. When trying to connect to our game, the host gets this error and the person cannot join. But we can join each other with empty map.
Now we have found out that if we put objects with saved in memo JSON of 3d locations(500 objects in average) in bags, then the map is loaded. We absolutely need them to be out of the bag. Does anyone have any ideas?