Pretty much exactly what the title says.

I have an iPhone that I'm preparing for an employee. We have never used deployment profiles for staff iPhones, so that's new.

The situation is we have a staff who resigned, I took his phone, and created an employee profile.

I then added this iPhone to the employee profile.

Long story short, I somehow got the iPhone unenrolled and it's now bricked.

I somehow managed to get it back re-enrolled, and I put it on the same profile I had it on before, except now no matter what, even if I don't assign it a profile, it simply says "The configuration for your iPhone could not be downloaded" and that the profile is invalid.

How do I unbrick this iPhone??