problem

[SantaSati]

# git push

  remote: Permission to NEUP-Net-Depart/mengxin-2018.git denied to ****.
  fatal: unable to access 'https://****：>>>>@github.com/NEUP-Net-Depart/mengxin-2018/': The       requested URL returned error: 403
  problem:I can't solve it.
##tip:**** is username,>>>> is key.

[VOID001]

@SantaSati You don't have permission to direct push in this repo

[SantaSati]

I built a new branch and then I merged them .At last,I committed ,pushed and got that:
$ git status
On branch master
Your branch is up to date with 'origin/master'.
nothing to commit, working tree clean
What should I do next ，and Is any error has happend？

[rayfalling]

see you upstream address. and if it is up-to-date. it's ok.

[VOID001]

I built a new branch and then I merged them .At last,I committed ,pushed and got that:

You cannot use command line git to merge your modification into this repo, you need to open a pull request.

$ git status
On branch master
Your branch is up to date with 'origin/master'.

This means your branch is the same as the remote branch. check what your remote address is. It probably be the address to your forked repo

nothing to commit, working tree clean
What should I do next ，and Is any error has happend？

You need to open a PR(pull request) to submit your changes to this repo

[Swinggcat]

Bravo! It's brave of you to speak up!