Are you trying to save an image from a tensor? if yes, then you need to specifiy the correct index.
e.g.
tensor1 has shape [64,3,28,28]
then to get one/first image out of it (the batch of 64), you need
image1_tensor= tensor1[0]
now you need to swap the axis to convert it into numpy
image1_numpy = image1_tensor.numpy()
Now if you save image1_numpy, you will get one image.