We are unable to upload an image

Whenever we try to upload an image to our form, we get an error message that says an image can't exceed 0Kb, even if the image is the size suggested (370x250)

The error shown indicates the max file size limit. It seems you've inadvertently changed the limit to zero that's why it keeps yielding an error. I fixed it for you. 

I fixed it for you. I changed it to 5000 (nearly 5MB) so it should work fine by now. The maximum file size allowed in now around 5MB.

Regards!