Filing an amendment for stae (NC) calculates me duplicate penalty

2018 NC return had a penalty of $30 (not big deal). I am trying to do an amendment  for it, because some deductions and credits I missed. I'll get refund a few $100s. As a consequence, penalty would decrease a bit (it's calculated to $27)

 

Turbotax is adding the full #27 penalty in the amendment, w/o discounting anyplace the original $30. So basically I'll have to pay penalty twice! In the past for similar situations, Turbotax would calculate the penalty in the amendment like -$3

 

Is it a bug or a change of tax rules? Any way of fixing it?