I've got a problem in a property my family rents out,2 light fittings are not not working there's power going to lampholder but still the light does not work,i took the bulb out of that fitting and put it in another light fitting and it is working fine,i've also taken the lampholder of the working fitting and put it on problem fitting and still it does not work,as i said before there is power to the lampholder on swithing on but the light just doesn't come on.any surgestions