Registration not working

Today I decided to take a look and find out why my traffic is leaving through the registration page but I am not getting any sign ups.
Turns out that you can't create an account, it just keeps going back to the registration fields, displaying the information that you have already input, minus the passwords.

I hadn't checked it in a while, didn't know I had to keep checking to see if it worked.

Anyone know what could be causing this?
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