Humanity Check Button Error

I've set up our new Forum Community within the past 48 hours. It seems to be working okay with one major exception:

After a new member registers and tries to log in to their account, after they put their User Name and Password into the proper places, when they attempt to do the simple math question to enter the answer into the space for humanity (identity) security the system is not accepting any typing into that frame.

Anyone out there able to help me get this working? I've quickly been able to find some people wanting  to use this forum but are unable to due to this system error.