Harassing - Sending emails on Sundays, sms and calling me before 08h00

I really need some advice with regards to a debit collecting company that is currently harassing me - MBD

I keep on receiving calls from them after I have made arrangements – They even went as far and start to send me whatsapp messages claiming that that were unable to reach me. I think this is absolutely wrong cause that send me all forms of correspondence to add extra costs from their side.

Furthermore it seems like they are not making notes because I have to tell them the same story over and over. They even sent me emails on Sundays afternoon. They are totally harassing me now. I have also asked them not to call me before 08h00 and at work however they ignore my requests