Children were turned away from C Too venue on Johnston Terrace
Parents have hit out at organisers of the Fringe after being turned away from double-booked children's shows.
BBC Scotland has learned at least two shows at the C Too venue in Johnston Terrace have been oversold.
About 20 parents and children were turned away on Tuesday from the Gruffalo and about 15 from the World's Greatest Bubble Show.
A Fringe box office spokesman said every effort was being made to resolve outstanding ticket issues.
He also advised ticket holders check the website for details of how to collect tickets for specific performances.
Maria Cleaver, 25, from New Zealand, was trying to take two children, one-year-old Matilda, and Poppy, three, to the World's Greatest Bubble Show.
She said "It was all rather chaotic. There was a long line at the two entrances. For a while both lines were moving, but ours suddenly stopped and we were told we couldn't get in.
"So we moved to the other line. They let a few more people through that one, but then the girl at the door said she couldn't allow any one else in because it would be a fire hazard.
"There were about 10 or 15 of us, all with tickets and young children, who couldn't get in.
"Every one left outside were really angry about the total lack of organisation."
Henrietta Walker, 36, from Edinburgh, booked to see four shows at the C Too venue.
She told BBC Scotland news website after receiving a "confusing email" from the Fringe box office she had tried to call every day for the past 10 days but the line was always engaged.
She also left three messages at the C venue box office without her call being returned.
Jane Reid, who was with her two-year-old Anders, said: "We were offered our money back or alternative dates for the show however the majority of us had already travelled to the venue with very small children, struggled down the very steep and un-parent/child friendly steps, waited for over 30 minutes to be told at the last minute that there was no more room in the theatre - try explaining that to a two-year-old.
"The lady in front of me had taken time off work especially to go to the show for her daughter's 2nd birthday. There were many angry parents and hysterical children."
It follows problems with the Fringe ticketing computer system.