🚨electricians or sparkies 🚨

this morning I was smelling electrical smoke in my hallway & I sniffed it out to the hallway light fixture 

what could have caused this one bulbs base to have melted & burnt out? 

these are early LED lights.  I’ve had them in this fixture for about 8-9 years. https://image.nostr.build/e5054a81bab4cdf7e5c860d69d24c1f648b5e82fce60be813eb4cd22e252431b.jpg https://image.nostr.build/b827b7b02581b57ab14b1576db108ba5bfb9a0fcbe61145384c98ab2ed15faca.jpg https://image.nostr.build/24ccbfaecdb47e74dd5e94da9d22c780bc47357bb03eac7c07949e15c0faad3e.jpg