Lightning cable corrosion on metal end

last night went to charge my iPhone 8+ so the USB end went in my Apple connector then into the regular power plug. I see that it isn't charging so i pull the bit out of my iPhone and see that the metal is all dis-coloured and the bits that are meant to be a gold color are now kinda black. Then the phone would beep everytime I moved it like the cord was loose or something sometimes getting power, sometimes not. I pulled out the lightning plug and looked at it only to find corrosion on the 'gold' connectors. Please help.