Electricians in Camden

I have five downlights in my kitchen that need checking. Three of them aren't working.
Surbiton Electrical Fault-finding

Drilled through power line in wall with small diameter drill. Line still carries current but insulation is damaged. Plaster and mortar removed and conduit opened to expose line, there is a hole though it although clearly not severing the wire
Tower Hamlets Electrical Fault-finding