Hi. When posting code, please mark it as having spoiler content, otherwise everyone on frontpage can see your code. Also format it properly (link here)

I don't know exactly how wrong it is, but I don't see you handling lower or upper case letters, to begin with...

Sample tests are just examples, there's a lot more tests run when you hit submit to make sure your solution is correct, and if you're getting errors, it probably means it isn't.