The man in charge of the Hollywood sign claims CGI was used in a video that appeared to show Sydney Sweeney decorating the landmark with dozens of bras.
A viral clip shared last week, which appeared to show the Euphoria star and a film crew accessing the tourist attraction, was recorded without permission, according to those who control the site.
Some have suggested there's no way they would have been able to get so close to the structure without police turning up.
Jeff Zarrinnam, head of the Hollywood Sign Trust, has insisted filming took place without authorisation, but is adamant parts of the footage were digitally altered.
Representatives for Sweeney have not replied to requests for comment.
