I'm on the more everything loyal 6gb plan if that makes any difference, I thought the loyal part was just for the data allotment though. Do you work in a verizon store or what? I always get the discount from their website chat support. My third line just went off contract this past December and I contacted them and they applied the discount, so it's there somewhere

I've had it on one of my lines since Nov 2015 so I don't know if that makes a difference (making it available on my account or whatnot)... had it added to my other two lines in sept and dec of 2016.
edit...
I just looked at my bill detail, the $25 discount that was added in 2015 reads as $25 OFF SMARTPHONE MONTH2MONTH the other two that were added in late 2016 read as $25 SP DEVICE PAYMENT DISC (one of those lines is on the apple IUP, and the other is on verizon monthly device payment)