He is described as white, five feet eleven inches tall, of slim build with shaved grey hair.
Chief Inspector Glen Doran, of Dorset Police, said: “We believe that Alan may be very upset and due to our concern for his welfare we need to find him as soon as possible.
“Following a number of enquiries, we have been able to obtain a CCTV image showing Alan on Saturday 31 July 2021 outside Nava Coffee in High Street, Ringwood, which shows the clothing he is very likely still wearing.
“Since our original appeal we have received some reports of sightings and I am grateful for this information.
“Unfortunately, we have not been able to find Alan yet and we are continuing our search.
“Also, I would like to renew my direct plea to Alan – if you see this appeal, please contact us or your family as everyone wants to ensure you are safe and well.”
Anyone with information or knowledge as to Alan’s whereabouts is asked to contact Dorset Police at www.dorset.police.uk, via email [email protected] or by calling 101, quoting incident number 31:259.