socket does not show up in blueprint

[Kiste_Becks]

Hi,

ive added a socket to this mesh:

dragged that mesh into my blueprint:

but on the right, when i enter socket it does not show “first”:

i can select Shape_Trim_90_Out or Static Mesh, first as socket does not exist.

Why?
Already saved the mesh multiple times, re added it to the viewport, but no luck.

[Kiste_Becks]

never mind, does not show up in blueprint but can be used in code:
AttachActors(this, ChildActor, TEXT(“first”));