I am having this same problem, and I have seen other parents on the help forum with the same issue, but I have not found a solution yet.
Hi @MeganDurst , @littlemomma424
This is an issue with the configuration of the form. It usually occurs if the grade field on the form has not been updated correctly. I suggest you report this error to the district directly because they would be able to review and update the field and assist you to proceed with the registration.
You can check out the FAQs related to the enrollment process here.