The family of Seafar man Paul Booth admit they are still at a loss as to what caused his disappearance last year.
Mr Booth (45) was last seen on the footbridge between McGregor Road and Hillcrest Road around 2pm on Tuesday, October 25, 2016.
Despite a major police appeal no credible information has been found to explain what happened to him.
His sister Pauline Gibson said: “I last spoke to Paul about a month before he disappeared, he called to see how my grandson who was born in July was doing, there was no indication anything was wrong until my brothers Gavin and Brian came to tell me he was missing.
“It appears his support worker went to visit him and there was no answer, when access was gained to the property they found it was empty apart from his dog, and his wallet, phone and keys were all there.
“Paul kept himself to himself, but his neighbours regularly saw him out walking his dog and we can’t believe he would intentionally leave it.
“Since he disappeared I’ve had all sorts of calls from people claiming to know his whereabouts, from working on a fishing boat in Aberdeen to sleeping rough in Glasgow, one person even said if we paid them £1000 they’d tell us where he is.
“There was one sighting reported, but after the police checked CCTV it turned out to be someone else.
“It’s just all so strange, and we just really want to know what happened to him, the police investigation has stalled because they have no good information to work with so if anyone knows anything I’d urge them to share it.”
Mr Booth is described as white, 5’10” in height, of slim build, with sallow skin, blue eyes, stubble and lightbrown cropped hair.
He has a slight scar on the right side of his face, his left ear is pierced and he walks with a slight limp. When he was last seen he was wearing a dark-coloured hooded top, jeans, white trainers and a beanie hat.
Inspector Phil Rose, Cumbernauld Police Office, said: “We made several appeals for information about Paul’s whereabouts, but have had no further sightings of him reported to us, or any details that may assist in finding him.
“Anyone with information should call Cumbernauld police office via 101 or email Lanarkshiremissingpersons@scotland.pnn.police.uk.”