Messed up my credit score!!!

Hello,

I’ve had two missed payments on my credit in December and January and it dropped my credit score by 18 points. How’s that possible when you’ve taken my money every month? But somehow you always sent an email to say I’m in arrears. Could you please fix this because you’re the one who’s supposed to collect your debits on time in my account and now my credit profile looks horrible because you’ve failed to do that.