I was promised a $300 gift card never got it

I got services with DirectTv back in feb 2019 ,I was promised a $300 gift card never got ,when I called the first time they re issued it ,this was back in March,I called again in Sept 2019 they said I could get what was promised because offer had expire ...I called reward center they never answered the phone lasted 1 1/2 and no luck,It’s about to be 8months and still no reward ,I was promised different amount for bundling my cell and internet together and the bad service has been on going ...