debit or charge

I need to write an email, Could you please help me make it natural and correct?

I just saw that $24,99 was charged to my account when I/it wasn't supposed to be charged. I Asked to cancel my account before the end of the trial period but no one got back to me. Conveniently, you got back to me after the end of the trial period and charged (for) a month. Could you please let me know how you work because this isn't right.

I just saw that $24,99 was debited from my account when I/it wasn't supposed to be charged. I Asked to cancel my account before the end of the trial period but no one got back to me. COnveniently, you got back to me after the end of the trial period and charged (for) a month. Could you please let me know how you work because this isn't right.

Which is correct or how should I use reimburse?
I also saw that you reimbursed $15,99 to/on my account when you were supposed to reimburse me $25,99.
I also saw that you reimbursed me $15,99 to/on my account when you were supposed to reimburse me $25,99.

Thank you so much