Empty promises

I have took my sister in law to buy the car at Mccarthy VWArcadia in November 2019.then after signing all the paper work ,they have confirm with me that they do pay for referral R 1000 00, i have asked which document they need for the referrals money payment ,they said i must submit 3 month bank statement,SARS confirmation letter and ID copy.i have been following up with the seens December ,sending email even walking to their office ,they keep on saying they will put petrol for me or pay R 1000.00 .when i went there in January they said it was supposed to be done in three month so they will process the claim and call me but even today Katlego Mokgatlhe ( New vehicle sales executive) VWArcadia haven't call me.