Unable to fetch from another fork of same repo github

Question

I have forked a repo from say user1/repo1 to me/repo1.

Another user has forked the same repo from user1/repo1 to user2/repo1.

I have read access to both repo. I can confirm because i can open the code in browser. I have cloned the forked version of my repo to local.

Now i want to fetch changes from user2/repo1/branchA. user2/repo was not in my remote list. So i added it using

git remote add https://github.com/user2/repo1.git

Verified using

git remote -v

and it shows the remote.Now when i am trying to fetch using

git fetch user2 
git fetch user2 branchA
git fetch user2/branchA

nothing works and i get fatal: repo not found

Also tried cloning the repo directly from link user2/repo1 to local using

git clone https://github.com/user2/repo1.git

but unable to do so. Github wont allow me to create a fork of another fork as i already have forked one version of the repo.

Already looked answers:

https://stackoverflow.com/questions/19971049/what-does-the-git-error-remote-repository-not-found-mean

https://help.github.com/articles/error-repository-not-found/

and various others as i am searching this from 4-5 hours.