I switched my iPhone 7P for an iPhone 8P, and I was wondering how do I make my old message history appear?

zairafromsevierville wrote:

And It wont let me add it to the back up

Restore the iPhone 8 Plus, from the most recent backup of your iPhone 7 Plus: Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

See: Transfer content from an iPhone, iPad, or iPod touch to a new device - Apple Support

Lawrence Finch wrote:

See: Transfer content from an iPhone, iPad, or iPod touch to a new device - Apple Support

I'll have to remember that new option. 🙂