Harrassment issue from Sino

I am so disappointed at the services and manager at Barko financial services in Parow cape town. I sent a message on their website complaining about one of their staff member Sino who came to my work place with one of her colleague who started harrassing me about missing one payment and I have been paying on time every month but this month I have a problem with my bank and they came to my work place. This was so unprofessional and very disrespectful.I have just received a call from her manager also unprofessional asking me how did I want Sino to speak to me instead of apologising as a manager for Sino's behaviour. Barko Manager I am not going to allow harrassment of any kind from your company. I still want Sino to come and apologise for what she did. I am very disappointed.