Have been given a wrong info. Branch manager cannot help. Is there a higher manager than can help us

I switched to att last October and got two phones under next. This was a branch in orlando. I was told by Curtis that for every number that we port in, we get a $100 credit. For every phone we turn in is $200 each. Bottom line, we ported 4 lines and surrendered 2 phones. I asked him several times, does that mean an 800 credit? He affirmed that several times again. He did not mention that you have to get a new phone under next to get the $100 plus surrender a phone to get the $200 total of $300. Now, am still expecting 2 $100 credit for the other two lines I ported In, but according to them and showed me the promo that ended last January that I do have to buy a phone under next to get the whole $300. Where is Curtis word that he was so sure saying that no matter if you do not buy the phone as long as you port in a number you get a $100 credit? Now am short $200. Went to their female branch manager but cannot help. Their sales rep does not know literally at that time the details of their promo. Am escalating this.