He was last seen in Ashtead on March 4.
Kelvin is described as a White man with grey, shoulder-length hair and was last seen wearing a black jacket and top.
He is known to visit Guildford and Sutton, and officers are urging people in those areas to keep an eye out.
Anyone who has seen Kelvin or has information on his whereabouts is asked to contact Surrey Police via direct message, quoting PR/45250026488.
