update my account with payments i made December

Hi. I am not happy with finchoice services. I took a contract phone with fine choice mid 2014. I have been paying them every month. In October 2015 I changed my banking details from abs a to std bank. End of November I notify finchoice that I have changed my blank ng details and they told me to pay it by hand in their Fnb account which they SMS the details. On the 1st December 2015 I deposited an amount of R170 to the account they SMS me. On the 4th December they debited my std bank account with R170. So I send them email with proof of payment to their email address [Email Removed] on several occasions but I get a call everyday to tell me my account is in arrears. The last email with proof of payment was send to them on the 7th Jan 2016. I'm tired of them harassing me with phonecalls whilst they are failing to update my payment send to them by email. What kind of a business are they running? They are *********** and slow. Please update my proof of payment before you call me again.