FNB and the Debt collectors

I am trying to see what can be done to get Groenewald Lubbe Inc to stop harassing me 50 times a week with various SMS's like below. All I ask for is some human decency. Ironically I have been paying constantly for years . I will pay it all. This stresses me out so much I will probably eventually be unable to pay. Thank you for your assistance. I have logged an complaint at CFDC as well

Mnr A Van Zyl, Final Warning, Legal action may proceed within in the next 3 days due to failed payment arrangement - urgently contact Patrick on *** Quote: CAL66341