Fine-tune can not exceed $15 during free trial,do this means i have to spend $15 dollars when im in paid plan?

ok . so this problem appeard when i m finetuneing .i searched through this community and the answers are telling me to upgrade to paid account .then the problem will be resolved .
but .
what is the meaning of exceed $15.
does this means i am gonna pay 15 dollars for a experimental model?
that is unaffordable for me !
can someone tell me the answer .
or if I am gonna pay $15 .how do a get to train a free model for experiment?