Max corruption isn't being calculated

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So as you can see from my gear I have 48 corruption total but I said to max it at 39 so I am not sure what is going on here.

My guess is that you did not make the recommended minor essence change to pick up the extra 10 corruption resistance.

Just did BiB off that Snapshot & got this:

Third Essence slot is Breath of the Dying, which gives +10 Corruption Resistance.