aitviewer, visualize error

[Kohki0401]

When I use simple romp below error happened. it seems to be from openGL context:
I already saw previous issue and tried to fix it, but it didnot solve

I used python3.8.1
--------------------------------------------------------------log ---------------------------------------------------------------
Traceback (most recent call last):
File "scripts/visualize-SMPL.py", line 101, in
viewer = HeadlessRenderer()
File "/home/datasynthesizer/miniconda3/envs/simple_romp/lib/python3.8/site-packages/aitviewer/headless.py", line 38, in init
super().init(**kwargs)
File "/home/datasynthesizer/miniconda3/envs/simple_romp/lib/python3.8/site-packages/aitviewer/viewer.py", line 72, in init
self.window = base_window_cls(
File "/home/datasynthesizer/miniconda3/envs/simple_romp/lib/python3.8/site-packages/moderngl_window/context/headless/window.py", line 23, in init
self.init_mgl_context()
File "/home/datasynthesizer/miniconda3/envs/simple_romp/lib/python3.8/site-packages/moderngl_window/context/headless/window.py", line 33, in init_mgl_context
self._ctx = moderngl.create_standalone_context(require=self.gl_version_code)
File "/home/datasynthesizer/miniconda3/envs/simple_romp/lib/python3.8/site-packages/moderngl/context.py", line 1667, in create_standalone_context
ctx.mglo, ctx.version_code = mgl.create_context(glversion=require, mode=mode, **settings)
File "/home/datasynthesizer/miniconda3/envs/simple_romp/lib/python3.8/site-packages/glcontext/init.py", line 90, in create
return x11.create_context(**kwargs)
Exception: (standalone) cannot create context