Can I exchange wrong color iPhone 17 Air after 14 days?

I have purchased the iPhone 17 air chose the black back. My phone arrived a few days later, but still had three weeks left on my current cell phone provider plan so I never opened the box when the time came for me to switch providers. I opened the box and it was the white back not the black back and then it said on the inside that I only had 14 days once the package was delivered to return it or exchange it for any inconsistencies. How can I fix this? Do I have to cancel my current cell phone plan and then sell the iPhone back to Apple to get the right color