Kick-off at the Stade de France was delayed for more than half-an-hour, with UEFA blaming fans with fake tickets trying to gain access to the stadium.
Police were forced to use tear gas and pepper spray on mostly Liverpool fans who tried to force their way in.
Robertson revealed he gave a genuine ticket to someone, who was prevented from entering because it was deemed as fake.
The final had originally been scheduled to be played at the Gazprom Arena in Russia but the country's invasion of Ukraine saw UEFA move the game to Paris.
"One of my mates got told it was a fake which I assure you it wasn't. It was a shambles really," Robertson told BBC Sport.
"To be honest people were just making it up at times and panicking. Tear gas getting thrown at people was unacceptable.
"It was horrendous for our fans and all families that have been through it as well. It wasn't a nice experience, not a nice final to come to. The Champions League should be a celebration but it wasn't that.
"Obviously the final wasn't meant to be here and whether the preparations were not as good as maybe they should have been but I am sure in the coming days an inquest will go into that."
Vinicius Junior's 59th minute goal saw Real Madrid beat Liverpool 1-0 to be crowned champions of Europe for a record-extending 14th time.
