IRS CP12 Notices Reducing Self Employment Tax

[joshuabarksatlcs]

Two clients received CP12's from the IRS reducing their Self Employment Tax.

One was reduced by $52 from $3,138; the other by $1,622 from $3,753. 

In each case, the client has taken the SE sick leave credit. 

On each CP12, the IRS noted the reduction amount and that the reduction was for SE Tax.  In each case, the AGI was increased by half of the reduction amount. 

I reviewed the numbers computed by Lacerte.  NO error noted.

Explanation, or similar experience, anyone??