[gender-age]AttributeError: 'NoneType' object has no attribute 'shape'

I have problem running test.py in gender-age
error message as follows:
PS E:\DataTraining\insightface-master\insightface-master> & "C:/Program Files/Python36/python.exe" e:/DataTraining/insightface-master/insightface-master/gender-age/test.py
loading ./model/model 0
[14:30:05] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:209: Loading symbol saved by previous version v1.3.0. Attempting to upgrade...
[14:30:05] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:217: Symbol successfully upgraded!
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:209: Loading symbol saved by previous version v0.8.0. Attempting to upgrade...
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:217: Symbol successfully upgraded!
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:209: Loading symbol saved by previous version v0.8.0. Attempting to upgrade...
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:217: Symbol successfully upgraded!
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:209: Loading symbol saved by previous version v0.8.0. Attempting to upgrade...
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:217: Symbol successfully upgraded!
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:209: Loading symbol saved by previous version v0.8.0. Attempting to upgrade...
[14:30:08] C:\Jenkins\workspace\mxnet-tag\mxnet\src\nnvm\legacy_json_util.cc:217: Symbol successfully upgraded!
Traceback (most recent call last):
File "e:/DataTraining/insightface-master/insightface-master/gender-age/test.py", line 29, in
img = model.get_input(img)
File "e:\DataTraining\insightface-master\insightface-master\gender-age\face_model.py", line 79, in get_input
ret = self.detector.detect_face(face_img, det_type=self.args.det)
File "e:\DataTraining\insightface-master\insightface-master\gender-age\mtcnn_detector.py", line 338, in detect_face
height, width, _ = img.shape
AttributeError: 'NoneType' object has no attribute 'shape'
---------------------------------
What is the problem I am facing?
What do I need to do to fix the error?
thanks.