Not able to change canvas size

[newoneatit]

When I try to change the canvas size of my image the result is the image becomes totally transparent and now after trying to fix it just becomes white.

Thanks in advance

[MarkZ]

Please provide more information.
- What are you starting with, an image, what format?
- describe the steps you take to change the canvas size
- are you using layers?
More information may give a clue to what is happening.

[newoneatit]

Thanks for responding discovered I had two layers and when I saved the image and tried it again I worked fine