MPOS (The standard open source pool front-end) has a set of triggers that automatically locks accounts in certain situations.  The most common is after a certain number of failed log in attempts, but there can be a host of custom reasons that the front-end could have triggered a lock.  I won't speak to that pool specifically but to say they have been around a while and there have been some complaints, most of which seem to always be resolved in one form or another.  I wouldn't expect there to be any scam a-foot.  I would send a support email and ask that your account be unlocked.  It is a simple matter of clicking a check box in the back-end of the GUI.