Thanks for the replies.
I have now had two electricians look into this. As mentioned earlier 3 of the sockets out of 8 stopped working suddenly. So the first electrician came in, looked at all the wall sockets and nothing wrong with them. The fusebox nothing tripped. He then carried out a test from the fusebox and said there is no continuity of Line/Neutral/CPC conductors for the ring final circuit in kitchen sockets. I don't know what this means but he asked whether I had any works done in the kitchen, I said no, I have lived here for 7 years we have not had any issues prior to this. He said there is a open circuit somewhere in the kitchen with no continuity and its a matter of finding where that wire or wires are located in the walls. He could not find this but having spoken to the previous owner he confirmed he used to have a fused spur and a socket in the kitchen which was taken out 8/9 years ago and the two wires may still be in the wall. The electrician advised section of the wall and kitchen tiles need to be removed so the wires can be terminated correctly and quoted accordingly.
I wasn't convinced with the above as we had no issues with the sockets all these years so a 2nd electrician came checked the sockets and when he looked at the cooker hood socket he asked there must be a isolator switch for this somewhere. There are 4 isolator switches in the kitchen and three were turned off. He turned them back on and all sockets are now working. For some reason someone turned of 3 switches but the issue has been resolved. However during his checks he established the kitchen is radial circuit and not ring. The kitchen circuit breaker is on 32a and he advised downrating this to 20amps. I mentioned about the two wires running vertically up inside the wall where the previous owner removed sockets, he used his voltage tester there was no live wires inside the wall, the wires would be dead wires he said. I mentioned about the open circuit with no continuity, he said if that was really true one or more of your wall sockets would not be working in the house. All the sockets are working in the house. Two grey wires together doesn't mean you have a final ring circuit in the kitchen. He said there is nothing to worry about just downrating kitchen circuit breaker to 20amps due to raidal circuit. Although the main issue has been solved who is right and wrong about the information given about this no continuity of Line/Neutral/CPC conductors for the ring final circuit in kitchen sockets?