If you just have a mobile contract with EE - have you recently also got a new phone from them as well? The charge for the phone will be a separate direct debit - although taken at the same time.
If you've got both mobile and broadband services from EE, I believe they'll be taken from separate Direct Debits.
If you don't have that and you're seeing you're being double charged each month, call billing and get them to double check what's going on?
