Hi there, I would start off by looking at the clutch slave cyinder. Which is bolted the to side of the gearbox bell housing by two 13mm nuts.
It may be that the rod that pushs the clutch arm is stuck out.
These cylinders are easy to change and are cheap to buy. A easy stating point. Just remember to bleed the new cylinder, if you fit one.
Hope this is helpfull
Regards Phil.........
bmw tech
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