AUPRC with imbalanced classes

Hi, it seems I am not getting expected results when using Performance (AUPRC) with highly imbalanced dataset.

The relationship between recall and precision of positive class seems pretty intuitive, but I still get AUPRC = 0.010 regardless of anything: 

I am using here imbalanced credit card fraud dataset.

At the same time when I artificially balance data, AUPRC shows expected 'normal' values:

Process attached:

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