My point was that you might be entering it in the wrong place in the software.  If you don't want to tell us the details, that severely limits any help anybody can give you.

In answer to your question, "passive activity" can be a completely different subject than if it is subject to SE tax.  So the check box is for telling the program if it is passive or not, but that doesn't necessarily affect whether it is subject to SE tax or not. 

If you think it is not subject to SE tax, then telling us why that is the case may help us to redirect you for how to enter it into the software (but it may depend on exactly why it is not subject to SE tax).