Failed to clone the project with recursive parameter

[XinliZ]

C:\GitHub>git clone --recursive https://github.com/asterycs/rtsr.git
Cloning into 'rtsr'...
remote: Enumerating objects: 697, done.
remote: Total 697 (delta 0), reused 0 (delta 0), pack-reused 697R

Receiving objects: 100% (697/697), 6.10 MiB | 7.30 MiB/s, done.
Resolving deltas: 100% (500/500), done.
Submodule 'libigl' (https://github.com/libigl/libigl.git) registered for path 'libigl'
Cloning into 'C:/Users/xlzou/Documents/GitHub/rtsr/libigl'...
remote: Enumerating objects: 20, done.
remote: Counting objects: 100% (20/20), done.
remote: Compressing objects: 100% (17/17), done.
remote: Total 35713 (delta 5), reused 2 (delta 0), pack-reused 35693
Receiving objects: 100% (35713/35713), 9.39 MiB | 8.31 MiB/s, done.
Resolving deltas: 100% (21808/21808), done.
error: Server does not allow request for unadvertised object 046744e43d7b98f5b4d1fa66cd69fc2b3793c20b
Fetched in submodule path 'libigl', but it did not contain 046744e43d7b98f5b4d1fa66cd69fc2b3793c20b. Direct fetching of that commit failed.