John was last seen on the morning of Saturday January 22.
Police said: "We are appealing for your help to find John.
"If you have seen him or have any information, please call us."
John is described as 6ft tall, with grey hair and glasses and is of slim build.
He was last seen wearing blue jeans and a blue coat.
If you have seen him or have any information, please call police on 101 quoting LC-20220122-0514.