[Koha] Kohadocs Git

Hi , Im trying to learn the way git is work in koha , I read some resources and I think I understand the basics . I do some changes to the files i want to edit kohadocs/ branch 3.6.x/ ar and some images but when i commit and push the changes kohadocs$ git push I have this message : fatal: The remote end hung up unexpectedly I dont know what is the problem and maybe i have to communicate with some people to give permeation to push my changes or I have other problem ? please help me :) and thanks Karam Qubsi Arab translating Team.