Can certain policies a school implements towards TPS beneficiaries be illegal?

I am a TPS beneficiary and a college student. Every 18 months, my status expires and I must submit an application to renew my TPS. During the re-registration period, my status is automatically extended by USCIS for 6 months (after the expiration date) to allow time for processing of the re-application. This information is available on the USCIS website. However, a representative of my college has told me that my ability to register for classes and pay for them as a resident for tuition purposes is dependent on the outcome of my re-registration, effectively blocking me from registering for classes (ultimately resulting in those classes being filled up and no longer available) despite the fact that my status is legal and has been officially extended. This has caused me great stress and aggravation, and has also resulted in months of lost time.