Unable to clone git on Ubuntu 16.04

[Rishabh Nigam]

I am unable to build the atomic engine. i am getting an error when i try to clone the git recursively as well as regularly.
--Regularly--
command run: git clone https://github.com/AtomicGameEngine/AtomicGameEngine.git

following message:
Cloning into 'AtomicGameEngine'...
remote: Counting objects: 55476, done.
error: RPC failed; curl 56 GnuTLS recv error (-9): A TLS packet with unexpected length was received.
fatal: The remote end hung up unexpectedly
fatal: early EOF
fatal: index-pack failed

--Recursively--
command run: git clone --recursive https://github.com/AtomicGameEngine/AtomicGameEngine

following message:
Cloning into 'AtomicGameEngine'...
remote: Counting objects: 55476, done.
remote: Total 55476 (delta 0), reused 0 (delta 0), pack-reused 55475
Receiving objects: 100% (55476/55476), 110.97 MiB | 107.00 KiB/s, done.
Resolving deltas: 100% (36473/36473), done.
Checking connectivity... done.
Submodule 'Submodules/AtomicExamples' (https://github.com/AtomicGameEngine/AtomicExamples) registered for path 'Submodules/AtomicExamples'
Submodule 'Submodules/CEF' (https://github.com/AtomicGameEngine/CEF3Binaries) registered for path 'Submodules/CEF'
Cloning into 'Submodules/AtomicExamples'...
remote: Counting objects: 8352, done.
error: RPC failed; curl 56 GnuTLS recv error (-9): A TLS packet with unexpected length was received.
fatal: The remote end hung up unexpectedly
fatal: early EOF
fatal: index-pack failed
fatal: clone of 'https://github.com/AtomicGameEngine/AtomicExamples' into submodule path 'Submodules/AtomicExamples' failed