The measurement of the differential cross-section as a function of p T (J/ψ J/ψ ) was incorrectly reported in the paper [1], due to an incorrect propagation of the efficiency values in the final analysis.In this erratum, all tables and figures that need to be corrected are reported, with identical numbering and captions to those in the orginial paper.In figure 2, only the data points are changed.In figure 9, the results of templated double parton scattering (DPS) fit for dσ(J/ψ J/ψ ) dp T (J/ψ J/ψ ) (the left column) are changed.In table 3, the percentages of the DPS component determined with p T (J/ψ J/ψ ) (the first row) are changed.In table 4, the σ eff values from the DPS fits for p T (J/ψ J/ψ ) (the first row) are changed.As a result, the values of σ eff for the models considered in the analysis are between 8.8 and 12.5 mb, instead of 10.0 and 12.5 mb.None of these changes affect the interpretation of the results and the conclusions.