This is not a bug, you've failed enough crimes lately to drop your crime experience that much you've dropped to a lower nervebar.
Of course it's easy to gain it back by doing safe crimes (and avoid getting jailed while doing so of course) the moment you do get jailed you lose another % of your total experience, making you drop even further. Once you've regained enough crime exp , you'll get your 43 nervebar back. Just like you increased your nervebar in the past.
Can be closed.
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