one pic error!... (Without change of Batch size)

I run this DCGAN in colab and I've only changed a few parameters(shown below).
The model was successfully lunched and the training process is good.
But there are " one pic error " every time the sample pic should be saved, so I got no images in the output folder.

Parameter changed:
"input_height", 96
"input_width", 96
"output_height", 48
"output_width", 48
"train", True
"crop", True
"visualize", True
"sample_freq", 10

Anyone who know how to solve this problem? Thanks for help.