Comed - WORST Client service ever, refuses to pay money back

They are totally unprofessional and their admin suck!!! They are quick to send out letters of demand but don't even make sure if the account at the Doctor is already paid up BEFORE sending demanding RED letters. Needless to say, account paid to Doctor in June and last week 7 October after receiving their RED letter and paid that as well, they now refuse to pay back my money I wrongly paid over to them as "I" need to confirm with the Doctor that they did receive the money 12 June. Seriously?? That's YOUR job, not mine, follow up on your own work!!! You must be ashamed of your service and promises to phone someone back which NEVER happens and if they do phone you back, you get answered with an attitude "I'm just delivering a message from my manager", no accountability. SHAME ON YOU!