What you have is a recessed nut. What you need is a normal nut. The bolt on the brake will be too short however.
You either need a new brake or you may be able to put the nut on inside the steerer tube. Might work well might be shit but it's cheap to try.
@Ant started
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What you have is a recessed nut. What you need is a normal nut. The bolt on the brake will be too short however.
You either need a new brake or you may be able to put the nut on inside the steerer tube. Might work well might be shit but it's cheap to try.