The space point finding seems to be generating incorrect doublet space points in some cases.

I have attached an example plot, the blue dots are points on a track and the red dots are not on a track. If the dot is filled it is a triplet and if it is not filled then it is a doublet.

The formatting of the details is as follows:
SP: x(mm),y(mm)
+ C: plane channel is_used npe

Tracker:1, Station:2
SP: 27.077350, -147.853421
+ C: 0 201.0 True 2.46755852843
+ C: 2 87.0 True 9.06126914661
UNASSIGNED:
+ C: 1 110.0 False 9.64406779661

As you can see the combination was done incorrectly and the one real hit was combined with a noise hit, followed by another real hit being unassigned to a space point.