paid provided proof but still being called

i just got call from agent calling from debt collection for telkom in gauteng from 011 calling from my private number she did not even confirm its the correct person saying im owing 1000 from november im like i sent proof of payement i paid last month aswel i suffered for almost a month tracing a payement i knew i made and telkom took so long to unsuspend my line i was on calls and emails it caused alot of stress only to get im sorry.this needs to go to the newspaper because im tired of telkom because know they dragging my name in the mud because of systems they dont update i have a bill that confirms they received my payements.