When updating your cover photo or campaign image, sometimes you may encounter a spinning wheel that makes it appear as though the image is not uploading. Most of the time, the image was successfully uploaded and you'll just need to refresh your browser.
Try doing a hard refresh of your browser:
PC: Ctrl + Shift + R
Mac: Cmd + Shift + R
After uploading a new photo you may still see the old image when viewing your campaigns or giving forms. When this happens, it could be that your web browser has cached the old image.
Try clearing your browser's cache: