There’s an off-hand moment early on in The Mummy when Egyptologist Jenny Halsey (Annabelle Wallis) draws attention to the importance of the discovery that she and Nick Mortion (Tom Cruise) have made by referring to the age of the sarcophagus: 5,000 years. Trouble is, Wallis clearly mouths “three”, not “five”. Oh well, ADR happens. Maybe there was a re-write where they realized that 3,000 years wasn’t enough for the Egyptian period they wanted. So they fixed it. That’s fine, if a bit distracting. Later, Tom Cruise calls “the chick” 3,000 years old. They left that one in. Maybe Tom Cruise is too busy to do ADR. Maybe no one caught it. Maybe no one cares.
Ladies and gentleman, this is The Mummy in a nutshell: falling over its own presumed intelligence, never paying enough attention to what it is doing for it to matter.