BMW BEST AUTO

On the 26th of October 2018, I took my car for inspection at BMW Best Auto in Rustenburg, they did a quotation on what needs to be replaced and I booked the car for the 1st of November 2018, took the car on the 1st of November 2018, they call me around 12h30 and said my car is finished its just going to the wash bay, when I get there I paid what was quoted and they told me that my V belt needs to be replaced, they quoted for the part and labour and told me to re-book my car, it only takes 30 minutes to replace the Vbelt. I am unhappy because I already booked my car twice with them in a space of a week, I have to pay labour again and rebook the car, where as there was enough time to replace the Vbelt because the job was finished at 12h30, the Vbelt was available at the store...