Oh I love your wallpaper, do you have a link to somewhere I can download it?

Thats interesting, I am using lineage as well (oneplus 6t) and do have the app com.android.devicelockcontroller. This could be some junk added when I enable the gapps magisk module which I generaly keep dissabled though.

In addition to the other resources people have linked if you are interested in learning more about this type of scam take a listen to
Darknet Diaries episode 141: The Pig Butcher, it is very interesting.

Reminds me of the four yorkshire men sketch