Hard Reset?

I read this online, so I'm not sure if it'll work. But you can try it, since you don't have many other options...

1. Open the dialer, and call *228, which will call Activation
2. Re activate your phone (option 1, I think...)
          a. some people have said that the dial pad isn't available during a call, so you can't choose an option. If this is the case, I think you can just end the call and do a new one to *22899 and it will go directly to activation.
3. Your new lock code will be the last 4 digits of your phone number

I don't really know if this will work. Use at your own risk, but it can't be too risky, because you're just reactivating your phone (I think). Hope this helps!

PS- if it's still the default code, it will be the last 4 digits of your phone number.