Make sure that you’re logged in to the same account that you’re trying to enroll with.
Make sure that UEFN is closed and launch Fortnite. From Fortnite, find Creative and launch it. Any work you do in Creative should count as a day once 24 hours pass.
If UEFN and Creative days don’t count, I am afraid your last option is to work in UE. Hopefully, that’s not bugged.