Sean Maurice, aged 29, is last known to have been in the London Road area at around 5pm on Sunday 4 July 2021.
He is described as being six feet and three inches tall, of slim build and with short brown hair.
When Sean was last seen he was wearing a red polo top and green tracksuit bottoms.
Inspector Vicki Withnall said: ‘We are very concerned for Sean’s welfare and are urging anybody who sees him or knows where he might be to contact us.
‘He also has connections to the Wandsworth, Clapham and Lambeth areas of Greater London.’
Anyone with information is asked to call Kent Police on 999 quoting 5-0896.