Hi I've used the following code.
But still doesn't seems to be working. Any suggestions please. Thank You.
I had this same problem and I fixed it with inline CSS that sets the display type to a block inside the <img> element. The "text-align: center" solution that is commonly suggested doesn't apply to images because... well, it's for text alignment rather than images.
<img style="display: block; margin-left: auto; margin-right: auto; width: 50%" src=(whatever your actual source is)>
You can change how large the image is with the "width" property.