Vodacom , incorrect data invoicing

Vodacom are not listening to me or treating me fairly , in fact i feel that they are *****ing my money. I was shocked to receive a SMS on 14 June 2019 informing me that i have used R1000 international data , i was in SA ? I logged an inquiry and was informed that billing is correct as i was roaming in Lesotho ? FACT is i was in Fouriesburg , Free State (which is approximately 10km from the Lesotho Border post at Lebowa) but i was NOT in Lesotho , I can proof this as my passport reflects that i entered Lesotho for the day on 15 June and i did not even take my phone with on the day trip , Vodacom simply confirms billing correct and is not interested in my concern or the proof i can produce ? So much for treating customers fairly