Other mistake: When the detective sends the traffic cam footage, a Gmail alert pops up. However, the dad is currently using Margot's computer, not his. He previously logged into Margot's gmail account on this computer so any alerts received would be Margot's mail, not his.
Other mistake: Sister Irene digs father Burke out of his grave in a crisp white night gown but doesn't get any dirt on it.
Other mistake: When Boyce and Ford are watching Chloe and the Nazi officer through the floorboards, the former are in the attic, the latter downstairs in the living room. Surely looking through the attic floorboards would only allow a view into one of the bedrooms. How then do Boyce and Ford manage to see down into the living room?
Other mistake: At the end of the movie Lorraine has to remind Elise that she helped her once, implying they haven't seen, or spoken since. When Elise first meets Josh in the 1st insidious she tells Josh that her and Lorraine have been friends for a long time, implying they talk or see each other regularly.
Suggested correction: That's debatable as the word "friend" does have to do with semantics. I have friends I have not spoken to in a long time, or speak with rarely, but still consider them friends due to our history. Others would say that's not a friend as that's not what they think of when they hear the word "friend." So it does depend on the individual person. It's also quite possible this is what they told Josh as the cover story for why she was contacted since they initially didn't want him to remember his past.
Other mistake: Dominica breaks her left leg and then holds her crutch (and the golf club) in her left hand. This is a frequent Hollywood mistake. If you are using a walking stick or a crutch, you hold it on the strong side, then the natural swing keeps it in sync with the injured leg and improves balance.
Other mistake: Daphne's dad drops the Legitimate Tulip badge in front of her so she'll avoid getting hurt, but when we see him do that, he does it before the warning for the ball is heard and seemingly not looking at the danger (especially in the second shot, when he is peeking from the corner). So his action makes no sense. (00:16:55)
Other mistake: When Vera returns to her house, a calendar with 2017 listed as the year can be seen on the wall. The present-day scenes take place in 2014, so there shouldn't be any reason for anyone to have a 2017 calendar. (00:56:55)
Other mistake: While Amy speaks with Bilel through Skype, each time Bilel is in the Internet cafe the same guy is sitting behind him.
Other mistake: When Michael borrows a cell phone on the train, he goes to the back to get a signal. In reality, walking around on a moving train does not do anything because you're already moving.
Other mistake: The opening text crawl stated that Ellen Taper Leigh (Annie's mother) died on April 3rd, 2018. But after the family return home after her funeral, the screen on Annie's laptop is shown at one point, and the date is listed as 10/9/2017. (00:00:25 - 00:06:51)
Other mistake: Bashir Salahuddin appears in the ending credits of the Italian localization as "Detective Summervile" with one L. It's a spelling mistake that appears also on IMDB, so one wonders if the localization team lifted name from the website, or if the theatrical version had the spelling mistake and was fixed afterwards.
Other mistake: When Tyler is in the bathroom brushing his teeth, he is facing a wall-sized vanity mirror. The mirror should not be able to reflect the window along the adjacent wall (along the right side). Also, regardless of what angle of Tyler the mirror is reflecting, it reflects the same image of the wall. (00:30:26)