Is it refurbished?

The first letter in the model number represents the source of the device. Currently, there are four known possible choices:

• "F": refurbished unit
• "M": retail unit
• "N": replacement unit
• "P": personalized (engraved) unit

iPhone X can still be functional, even up till today. If you put a phone in a shelf and don't use it for quite a while, the battery FCC(full charge capacity) will decrease, but will not make the phone malfunction. Lots of my friends still own an iPhone X and are they are working perfectly fine. After nearly three years, you may need a battery switch, but your phone won't have hardware problems.

Here is how to Determine if iPhone is New, Refurbished, Replacement, or Personalized:

• M – Brand new device, meaning the device was purchased new
• F – Refurbished device, meaning the device has been through refurbishing process
• N – Replacement device, meaning the originally bought device was replaced by this model likely due to a service request
• P – Personalized device with engraving, meaning the device was customized with an engraving on purchase

You are correct. If your serial number starts with a F then it is a refurbished iPhone. Contact your seller and inquire about it. If you paid full price for it then return it and demand a brand new iPhone.

Axel F.

The iphone X was discontinued almost 2 years ago.

If it was a brand new device, it would have been sitting on a shelf with the battery deteriorating over that time. Most likely it wouldn't be functional.

batteries lose charge overtime.

once a lithium ion battery deep discharges, it’s dead.

Sitting on a shelf in a warehouse for 2 years may very well cause a battery to drop to zero and stay there.

my statement has nothing to do with a phone in use and being regularly charged.