Why did I not get autopay discount on all Magenta lines?

I signed up for the Magenta 55+ with 3 lines. All the online pricing quotes show final price of $120 and then $105 with $15 autopay applied (3 lines @ $5 each). In store it was confirmed. The next day, after signup, I log onto T-Mobile and the pricing show $110 ($120-$10 autopay discount). I called the T-Mobile store and representative that help me signup confirmed should be $105 and I should wait for the bill to see if it changes. I was in the store again today and the store manager confirmed should be $105 with $15 discount not $10. She mentioned she had never seen that happen before. She also suggested waiting until the bill is generated. So, I get home and receive a text message that the bill is available and as expected Total Due $110 (not $105) including a $10 autopay discount. Account shows 3 active lines being charged: 2 Lines $70 and 3rd Line $40.