How can I fix my 28" Matsui DWO1 Digital TV?

It seems to be locked out as when switched on a flashing sign PROTECTED appears with box below for owner's name. After few seconds the set switches off. The set has never been programmed with a PIN code or owner's name. Prior to this, set was working perfectly until I tried to discover why DVD wasn't working. Must have pressed something on remote to lock the TV.