I had a botched arrival into LEBL tonight. I had BISBA marked as the start of my STAR, and no waypoints after that. Shortly before reaching BISBA, ATC vectored me on to a different heading and ordered a descent to 29000 with vectors for runway 02. After that, I got no further instructions -- I ended up way too high on the descent, and ended up putting myself into a hold with speedbrakes and gear out to get down to where I was supposed to be.
I'm wondering two things: why did I start getting vectors when I had a STAR configured, and how come once I started getting vectors I was abandoned.
(Both of there are probably because I messed up somewhere along the lines, but I don't know how.

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