The bride-to-be, a Rutgers grad formerly of Union Township, explained that she had planned on trying it on for her own wedding.
But when Pereira took the dress out of the box last month, she and her mother discovered that someone else's dress was inside.
"My mother was heartbroken and tears when she finally opened up her wedding dress which she had preserved for 30 years so I can try on for my wedding," Pereira captioned a video shared to Facebook and TikTok.
"When we opened up the box we [realized] that this dress is not her wedding dress and the business she used to preserve the dress is no longer around."
The family tells NJ Advance Media that they believe the dress was accidentally swapped with someone else's as the now-defunct East Side Cleaners in Newark, where Pereira's mother had her dressed cleaned after her wedding.
The outlet says Pereira's mother, Christina Pereira, wore the dress when she wed Luis Pereira in 1994.
As of press time, Pereira's video had been watched 54K times on Facebook and 786K times on TikTok.
Pereira is urging anyone who knows where the dress is to reach out to her.
Click here to follow Daily Voice Saddle Brook-Elmwood Park and receive free news updates.