I upgraded my phone recently to x Max and it's passed 14 days, however, the phone is unopened along with accessories.
Does an unopened phone still fall within the 14 day return policy?
Not if it is after the 14 days as you have stated. It is not 14 days from when you open the box but 14 days from your point of purchase. The only exception to this is around Christmas when Verizon gives you extra time until late January.