Thanks for your post @Kwak I'm sorry for the numerous duplicated billing emails you've received. I've discussed this with a colleague from our billing team and the good news is that this isn't affecting your actual account billing as the system which sends out the notifications is different from the system that generates your bills.
I've raised this for further investigation, however I'm afraid I'd be unable to advise when this will be sorted but we'll work as quickly as we can to. It's possible this may resolve itself by your next bill date though if we don't fix it sooner.
Apologies for any inconvenience this causes, and let us know how it goes.
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