What exactly at you trying to do? Just reset the win/loss record and start over with the starter team and no coins or bench players? If you can be a little more specific in what you are trying to do, we might have a better chance of giving you useful information on how to solve your problem.
Also you should understand that Answer HQ is not EA Customer support or a direct line to the developers. Hostile posts accomplish nothing here but make people less likely to try to help you.
Everything I can find says you can't just start over if you want to use the same gamertag. One solution though would be to create a new gamertag on the same console and go into Ultimate Team mode. Since it's a different GT, you should be starting fresh. It sounds like it's a feature that lots of users would like, but I can't find any information on how to do it. I will try when I get home to see if I can figure it out, but I, at least 6 hours from that.
In the mean time try contacting EA via social media and letting them know you would like to see the feature added. It sounds like you are not the only one, so possibly with enough support you could see that feature added to a future title.
Facebook:
https://m.facebook.com/EASportsMUT
Twitter:
https://mobile.twitter.com/EASPORTS_MUT
Forums:
http://forum.ea.com/eaforum/categories/show/221.page
