If you just got a new iPhone 15 device, before transferring your data from an older phone, make sure to update that new phone to iOS 17.0.2 first. A Apple Support Document says the update, which came out Thursday, fixes an issue that “may prevent data transfer directly from another iPhone during setup” (through MacRumors).
Please note that iOS 17.0.2 is only available for newly released iPhone 15 phones; The most current software for older iPhones is iOS 17.0.1, which was also released on Thursday and included some important security updates. After trying to initiate a transfer, your new phone may prompt you to update; At least, that’s what happened to a colleague of mine in The edge.
The iPhone 15 and iPhone 15 Pro are officially available starting Friday, bringing updates like USB-C ports, updated external designs (titanium for the Pro models!), and improved cameras.