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It won’t work this way due to initial rigid body motions which are not allowed in static analyses. You should fix all RBMs of both parts. Contact is often insufficient for that, especially when there are initial gaps. There are multiple ways to handle this but the most common ones are using prescribed displacement/rotation instead of force/torque, making sure that contact is established before applying the actual loading or even using soft springs to stabilize some problematic directions.

Start from a simple shaft subjected to torsion, add similar features like here and try to get it working. Then proceed to this complex model.