Custom head coaches are stuck unemployed

[Indestructible]

I created a custom database with 6 custom managers just to simulate and see how they do. I gave them 20 ambition and randomized the rest of their stats. Now, over 4 years into the future, 4 of them have been sacked and are just sitting there unemployed. 2 of them have been unemployed for 3 or 4 years and still have not gotten new teams. I feel like I've done something wrong in the setup. Is there any stat that prevents them from joining new teams?