Not impressed bout Vodacoms customer service

Took phone from them (credit) ,owhh the way they've been calling me before I took the phone ,telling me nice things and also telling me about insurance. Fine no problem ,problem started when I asked them to debit the money on a specific date and they wouldn't do that sent them email no response, I ended up just paying through my bank app. Lost my phone I think 2 months after taking it ,only paid 1 month for the insurance, now I keep on sending them emails wanting to know if I'll be able to get another phone or not . I don't get any response from them all they do is just sent me invoices of how much I need to pay,I just decided not to pay cause they don't respond .All emails ive been writingfor them ill be leaving my alternatenumber but nothing,I know it's bad on my side but where's the communication. I don't mind if am not gonna get a new phone all I wanna know is to know way forward and communication that's all