My trunk opens on its own.
It sounds like there is a problem with the electronic trunk release. The button may be shorting out and telling the latch to open on its own. The problem could also be that the trunk isn’t fully closing. Try pulling up on it when it’s closed. If it can still open, the latch may need adjusted or replaced. If it is the button, you can unplug it until you can find a trained technician to diagnose and repair your trunk.