ACS and Mr Price Account- Stop calling me please!!!

I was in an accident and my finances were affected dearly, i was handed over to your debt collection department (ACS) due to not being able to afford my monthly account repayments.

I've since entered into a payment arrangement and diligently pay more than what i agreed on the 25th of every month.

Despite this, i still get called by your staff members almost every day, every single month, mostly to say "THANK YOU" for paying my account (which is unnecessary and i get billed for this), and then again thereafter to make a payment arrangement again (which is also unnecessary since i entered into a payment arrangement months ago).

Whilst i understand that phone calls to most people are necessary in order to facilitate payment, I have not once defaulted on my payment arrangement and would appreciate your staff not calling me at work ALL the time!

I also requested a statement of my account and the amount I have paid thus far, does not correspond with the balance on my account....Please look into this as it is very frustrating to honour my payments but my account is still on a standstill. HOW???