After more than 15 years covering everything Apple, it’s with a heavy heart we announce that we will no longer be publishing new content on iMore and the iMore forums will be closing as of November 1st, 2024.
From whom did you order/reserve your phone? If it's Apple go to Apple.com, click on the little shopping bag icon in the upper right corner of the page and go to Orders. You will have to sign in. but from there you should be able to see your order/reservation.
If you ordered from someone else, check with that company's website or customer support.