Each of this could help

1. Confirm if you are still connected using ssh. Type this: ssh -T [email protected]

If you get the message that you were successfully authenticated and that github doesn't suppoet shell access then you can trying pushing your code again.

2)Create a new ssh key, add it to github and test it using ssh -T [email protected]

Each of this could help

1. Confirm if you are still connected using ssh. Type this:

ssh -T [email protected] 

If you get the message that you were successfully authenticated and that GitHub doesn't support shell access, then you can try pushing your code again.

2. If the above did not work, create a new ssh key, add it to Github, and run the command again:

ssh -T [email protected]