French title for English language UPC

I tried to scan the actual UPC of Mordenkainen Presents: Monsters of the Multiverse ISBN: 978-0786967872 in my app. US user, never set up any language other than English. It comes up with the French title. les monstres du multivers. The info inside looks English, has other user tags, everything, but it comes up French.
I came to the website and searched for the title: Got the English version.
I searched for the ISBN (same I scanned) and it came up English.
Rescanned and retyped in the same ISBN as above into my app: French.
I haven't used the app in a couple of years, to be honest, but I never had any settings in the site or app for French. It's been way too long since I spoke it to be able to be good enough at it to set my apps with it.
Any reason the app's scan will insist on another language other than the book is in, when the website has it correctly?

What source are you using? The data comes from a source, and not from LT.

Mordenkainen Presents: Monsters of the Multiverse

>1 hnbrink: I'm only seeing one copy (the English version) in your library. In the app, as MarthaJeanne mentions, what data source/s are you searching?