Buffalo City Municipal Arrears

Good day My father passed away 2015 and the house was sold 2018 now I'm recieving calls from BCM lawyer that i owe them R120 000 which they are me and the new owner. I've tried contacting them since i don't stay in KWT.A month ago i sent them the proof that the house was sold 2018 and now they're telling about the house in PE that is not under BCM but under NMM and its up to date...Can someone please assist me regarding