GitHub-Settings for Plugin "Backup your vault with Git" fail


I need to create a branch in my git repository.
To do this, I log in with the terminal command

" git clone".

The last step in the process is to enter the password. Here the access fails not because of missing password, but because an input is definitely not possible. It is in fact blocked.

My question:
How can I unblock this blocking brake, so I can continue with entering my password.

Many thanks for your support