Models lose interest once they make money

Hello, I'm coming with a problem I'm facing, maybe someone here has faced it before.

I’m working with independent models on CB mainly, bringing traffic. Everything is fine so far, I started with some models that did not have high incomes (less than 1-2k per month), at the beginning the models were very involved but as the time passed and the incomes increased (not that high but around 10-15k per month), they started not keeping to the schedule very well and in short a total lack of interest.

I thought that if I give them freedom, don't stress them and just promote them in my own way without getting involved in their lives, everything will go well, but it's not quite like that, especially from my point of view, because I know the potential and they are happy when they see just a little growth.

I stopped working with many models, after they came back to me because they no longer had the same results.

Any advices? I think there are girls here who over time have come to generate consistent incomes and may have faced this problem of no longer being interested and serious in work.