Correctly and incorrectly titled sequels

Correct:
"Now You See Me: Now You Don't"
"Ready or Not 2: Here I Come"

Incorrect:
"Now You See Me 2"
"I Still Know What You Did Last Summer" which happens another year after the original
Anything horror film called "The Last Chapter" or similar

M3gan 2.0 instead of 2 Fast 2 M3gan

I Know What You Did Two Summers Ago, And Also What You Did The Summer After That

incorrect:
Top Gun: Maverick (people are expecting characters from the movie Maverick)

the writer of the Now You See Mees and the director of the first both fought the studio to try and keep the second one titled Now You Don’t.

There's a whole subgenre of Italian sequels to US horror films that use the Italian name instead. In Italy Dawn of the Dead was released as Zombi, and there was a completely unrelated Italian sequel called Zombi 2, which confusingly was released in the United States as Zombie (and in the UK as Zombie Flesh Eaters). And in Germany Day of the Dead was released as Zombie 2 (and Zombi 2 was released as a completely separate film called Woodoo).

A similar thing happened to the Evil Dead films, which came out in Italy as La Casa. And then two instalments of the House series were marketed as part of the same franchise, which makes a certain amount of sense because "casa" is the Italian for house. And for the first time in what must be fifteen or even twenty years I have just thought of the Barbie movie. Do you remember what it was the most important film ever? Ah, happy days. I have also just thought about Danny Cannon for the first time in what must be twenty years.

There are apparently at least five different films called Zombie 3 or Zombi 3 or Zombi III etc:
https://en.wikipedia.org/wiki/Zombi_(film_series)

The other famous example is Troll 2, a film that has no trolls in it - it has goblins instead - but was marked as a sequel to Troll because why not.

This list fascinating as well, and reveals that (a) there were sequels to Lake Placid! (b) people were really scared of bees in the mid-1970s:
https://en.wikipedia.org/wiki/List_of_natural_horror_films

Like, really, really scared.

‘Say Cheese and Die - Again!’ (RL Stine/Goosebumps)