Unpaid account

I was working for Woolworths Financial Services and resigned December 2016. I had a store account with them and they deducted the outstanding balance on my last salary. Thursday 2019/11/07 I received a call from lawyers informing that I owe Woolworths R897 I have never received a call from Woolworths and they have the decency to take me to the lawyers without informing me. All these years how could they have picked it up now only I am so disappointed in the way the matter was handled.