Suspended account treated unfairly

You weren't reported on 17/2/17,that was when your suspension started.

You wont be told when you were reported.

As the enforcement team don't use the forums you would need to log on to the enforcement site to see why you were suspended & file for a case review if eligible
http://enforcement.xbox.com/home

I have been doing this but yet my reputation has yet to change

Unfortunately, due to the low reputation, you will only be able to play with others with similar reputations or play in private matches with friends. This will be the only way that you can raise your reputation back up to play with a wider selection of gamers.

Your warning is the code of conduct you agreed to when you singed up. Per the terms you agreed to, you are responsible for your account at all times. It's also a violated to let anyone use your account.

This would be the warning right here - https://enforcement.xbox.com/en-US/home/codeofconduct