Lied to about Visa Gift Card that never arrives

Just as I thought, I am not the only customer that got lied to and never received their Visa Gift Card.  For almost a year ATT was laying the cables in the ground in the newer community we moved into.  They screwed up so many peoples lawns, most my neighbors refused to upgrade, the few that did had nothing but problems for months.  I waited until all the construction work was done so that the install would be simplified.  I had been overcharge by 
ATT and they hadn't refunded me so I contacted them by phone.  During this time again I was hit over and over with the offer to upgrade to Fiber Optic, she told me that I was eligible for $150 Visa Gift Card if I did so at this time so I agreed.  Installation of the cable took place the next morning, so I obviously held up my end of the bargain - but here it is over 4 months later and no Gift Card, even worse, they never came to bury the Fiber Cable and it is strewn from one side of my home to around the entire backyard and then up the other side of the house.  Every time I have my lawn done I have to make sure the cable doesn't get cut!!!  Now however they keep trying to say they will 'credit my account' for $150 instead of the Visa Gift Card!?!? NO I don't think so!  I have always paid my bills on time, I no longer have a landline,  I no longer have cable, the only thing I have with ATT is Internet.  I am already waiting for $40 to be refunded to me that I was overcharged months ago, you think I want you keeping $150 in my account instead of sending it to me in a gift card as promised....pretty sure that's considered fraud.