You'll have to ask the organization that issued the 1099-Misc. If they issued a 1099-Misc, they probably think it's taxable. Some plans, like you describe, are Taxable. The $5250 limit for tax free assistance is for employer plans and that doesn't sound like what you got.
"However, unlike other options, student loan forgiveness under an income-driven repayment plan is taxable."
https://www.savingforcollege.com/article/student-loan-forgiveness-for-first-responders