I have googled and found many solutions but none work for me.
I am trying to clone from one machine by connecting to the remote server which is in the LAN network.
In my case it was a connection problem. I was connected to an internal wifi network, in which I had limited access to ressources. That was letting git do the fetch but at a certain time it crashed. This means it can be a network-connection problem. Check if everything is running properly: Antivirus, Firewall, etc.
The answer of elin3t is therefore important because ssh improves the performance of the downloading so that network problems can be avoided