Problem
Reported error: error: The requested URL returned error: 401 Unauthorized while accessing
git version: 1.7.1

Solution 1: Specify the user
git clone https://github.com/org/project.git
Replace it with
git clone https://[email protected]/org/project.git
or
git clone https://username:[email protected]/org/project.git
If it appears in push or pull, you need to change the remote address
git remote-set-url origin https://[email protected]/org/project.git

Solution 2: Remove authentication
git config -global http.sslverify false

Solution 3: (recommended)
Upgrade git to version ≥ 1.7.10

Solution 4
Add ssh secret key