SetBinLabel, labels disapear if read and write, update TGraph

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First I create a TGraph, and i save it to the file.

TFile *file1= new TFile(somepath,“recreate”);

TGraphErrors *h_tpc_event_recvertex_0 = new TGraphErrors();
h_tpc_event_recvertex_0->Write(“h_tpc_event_recvertex_0”);

file1->Close();

Now I Open the TGraph (in the different macro):
And I set in the bin with label ‘1’ new label ‘myLabel1’

TFile file2(somepath,“UPDATE”);

TGraphErrors *h_tpc_event_recvertex_0;
file2.GetObject(“h_tpc_event_recvertex_0”,h_tpc_event_recvertex_0);

h_tpc_event_recvertex_0->SetPoint(0,1,recVertexX[0]);
h_tpc_event_recvertex_0->SetPointError(0,0,recVertexX[1]);

Int_t binNumber= h_tpc_event_recvertex_0->GetXaxis()->FindBin(1);
h_tpc_event_recvertex_0->GetXaxis()->SetBinLabel(binNumber,“myLabel1”);

h_tpc_event_recvertex_0->Write(“h_tpc_event_recvertex_0”,TObject::kOverwrite);

file2.Write();

Now If I Open the TGraph again and, just Open it and Save, the labels I set disapear:

File file2(somepath,“UPDATE”);

TGraphErrors *h_tpc_event_recvertex_0;
file2.GetObject(“h_tpc_event_recvertex_0”,h_tpc_event_recvertex_0);

h_tpc_event_recvertex_0->Write(“h_tpc_event_recvertex_0”,TObject::kOverwrite);

file2.Write();

My prediction is that when openning TGraph it does not open axis to, but I don’t know how to fix it.
Please help and sorry for not precise first post.