Target Promotion

I was called on March 21st by Xfinity and they left a voicemail saying my bill would go up by $50 if I didn't immediately call this number back. Once I was finished with work meetings, I called the number back and was told about a promotion with Target where you get a locked in rate of $90/month for 3 years. In short, the promotion centers around either paying 6 months of your new monthly bill of $90 by either buying target gift cards or opening at Target credit card. I opted for the Target gift cards. That same day (Friday, March 21st), I purchased two gift cards at Kroger where we live....called Xfinity back relayed the gift card info and went about my day. Fast forward to today, March 24th...I get a text saying there's an issue with your account. Please call. Called...rep said there was an issue with the gift cards and I need to purchase 2 more for $540 that i would be refunded the original $540 + an extra $100. The rep did state to call from the parking lot, but did not explain why I needed to call from the parking lot. I purchased two more cards (during my work day) came home to call the rep back with the info and low and behold they are also flagged. All of this seems very fishy/scam like. He explained to me that I need to be in the parking lot as they are linked to 'their system' (don't know what that means). So now I'm on my way to get a THIRD SET of gift cards for this so called promotion. If I do not get my 1280 back in the mail tomorrow, I will be taking legal action. This is absolutely ridiculous. 

Representatives need to explain things clearly for the customer to understand the process as i don't make it a habit to sit in my car with $540 worth of gift cards speaking to my internet provider. Absolutely ridiculous.