change cable termination via API

[Frank17489]

I change the termination to a switch interface
(PATCH): https://{server}/api/dcim/cables/{id}

json: {
b_terminations => [
{
object_id => 18402,
object_type => "dcim.interface",
},
]
} # 18402 is the correct interface-id

the webcall has no errors. the changes a done and visible.

on cable page status: connected
but the status in interface page is not reachable
the cable trace page shows no path found

It works if I change this manually.

whats wrong? Must I send another call to rebuild the cable-path?

what means not reachable ?