Edgar completed the move on January deadline day in a deal which was set to run until the end of the season.
But it was revealed on Wednesday that a slight administrative discrepancy - one decimal point being out of place in Burnley's paperwork - had meant clearance for the switch from an English club to a Welsh club had been blocked by the game's world governing body, despite ratification from the Football League and Football Association of Wales
The Canada international has now formally returned to Turf Moor, with Swans boss Brendan Rodgers telling City`s official website: "I feel for the player.
"Every day he was here you could see he was getting more disappointed because he couldn`t play.
"But we`ve got to look after our group and at least David will get a chance to play some games back at Burnley."
Source: PA
Source: PA