❔ EntityFramework many-to-many relation does not work

Question: I have two database tables, one for users called

DataUser

DataUser

, and one to define a relation between two users, called

DataUserLike

DataUserLike

. I defined a many-to-many relation in

DataUser

DataUser

which both go directly into a collection of

DataUser

DataUser

(LikedUsers & LikedByUsers), and below that I define the

DataUserLike

DataUserLike

table to use as a seperate entity. This also uses a collection (Likes & LikedBy ). When I add relation by inserting a

DataUserLike

DataUserLike

instance into the database, I can see it properly added into the database. However, when I try to retrieve the users, both mapped and unmapped, the collections remain empty. Does anybody know what I did wrong, and what I have to do to show the likes in the collections?
https://hastebin.com/voxawutiko.csharp