James Allan tried to rob a newsagents in Northcourt Road, Abingdon, Oxfordshire, on March 2, using a toy gun.
But his efforts failed when he stumbled into a drinks container and couldn't open the door to escape.
He had also tried to rob the newsagents ten days earlier.
Police released the CCTV video after James Allan, 29, of no fixed address, was sentenced on Thursday to two and a half years by Oxford Crown Court for the first robbery.
Allan is already serving three years in prison for the second robbery shown in the video. His sentences will run concurrently.
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