This is my proof. I signed up for DirecTV 2 year price lock from this website. I clicked on the link and chose my package and was able to lock in my price for 2 years. By allowing resellers of their service DirecTV is obligated to follow though with the terms of the agreement.
This is expired but maybe was not when you signed up.
I copied this and pasted it here from the ad.
DirecTV is offering users a chance to lock prices for 2 years. Note that the 2nd year is more expensive than the first, but you are still locked in to a sale price. This offer expires 7/18. Plans range from $29.99/mo. Choose the package that best suits you, some of which include: