Good afternoon, I have a problem with no power to sockets in my Extension we had completed 2 yr ago. All sockets on RC board are switched on, downstairs sockets work only in the area before the electrical works. It tripped 4 days ago and we put back on until this morning plugging appliance on then a went off and now no power, again only in area we had additional sockets added. Any help on what it could be ? Tks