Getentry not work for leaves with similar name but end with different "_"

Hello, I’m using root 6.02
I try to write a marco to read root file by this:

Float_t DsvpvDistance[Max_Dsize];
Float_t DsvpvDistance_2D[Max_Dsize];

ie, in the root file , there are two leaves with similar name “DsvpvDistance” and “DsvpvDistance_2D”, one end up with additional “_2D”,
when nt->GetEntry(i), for some root file it works, but for some files the DsvpvDistance[iDsize] will not be able to read and are all 0.

This probelm seems to be solved by adding and changing :
TBranch *b_DsvpvDistance;
nt->SetBranchAddress(“DsvpvDistance”, DsvpvDistance, &b_DsvpvDistance);

but why does it happen?

nt->SetBranchAddress("DsvpvDistance",DsvpvDistance); nt->SetBranchAddress("DsvpvDistance_2D",DsvpvDistance); Is it just a copy/paste error or are the two variable the same (2nd parameters)?