How many starting companions can you have in your party

So I'm just starting a custom party, I want to start with me and 2 other characters, and so I write about them in the story settings thing when creating the scenario and it works, the ai knows about them, but never adds them to the party. I ask it to add them to the party myself, and it only adds one of them, so there is me and one other companion. When I ask it to add the third character to my party, it doesn't, and just says things like they are already in the party and the character share dialogues saying that are in the party with me etc, but the game hasn't added them as a companion. is this because you can only one one companion? Or does anyone know how to fix this?