fedpkg clone -a kernel failed

I am trying to build custom kernel on Fedora-34 following this quick-doc https://docs.fedoraproject.org/en-US/quick-docs/kernel/build-custom-kernel/ I got error: # fedpkg clone -a kernel Cloning into 'kernel'... remote: Enumerating objects: 2656, done. remote: Counting objects: 100% (2656/2656), done. remote: Compressing objects: 100% (926/926), done. fetch-pack: unexpected disconnect while reading sideband packet fatal: early EOF fatal: fetch-pack: invalid index-pack output Could not execute clone: Failed to execute command. This is my first time trying to do that. Please help.