alamo rental car charge me for fuel when it was return full inglewood, California

on oct 11, 2011 i return at alamo rental car in lax rented from ontario airport for one day which this was pay by a voucher from happy cars co. later in day when i get my credit car statement i see a $51 charge from alamo. I email them asking why they say it was for fuel, well i respond that was not correct. explain that I stop by and fuel the car and it was full and more. gave them details that due to the miles i drove it was inpossible for me to had use all the fuel to check and check that a mistake has to be found. how can a car be fuel when is full. maybe fraud in their company is happening.

I ask for the CEO contact information but nothing. I can not get any information to contact someone that maybe is not a crook in that company and understand that this is wrong and probably from what i read online there are 100's of complains against alamo all have to do with overcharge. this has cause me lot of stress since i live on a very tight budget and this has cause tremandous stress and I'm a heart attack patience and should not be stress but they dont care. it looks their customer service is one of those done in India or outsource and what do they care is another world .. let those americans die who cares.. I hope the CEO of alamo reads this one day and can have a heart and do what is right..  anyone can help me with the email for the CEO will appreciate.