Hello sergei85 and welcome to Apple Support Communities.
I see you are trying to reconcile a backup created using a different Apple ID with the Apple ID you currently plan to use for a new iPhone.
There is no way to directly transfer a backup file between Apple IDs. A backup is forever tied to the Apple ID used to create it. However, you can take these steps to get to where you're trying to go.
1) Sign in to the old Apple ID on the new device
2) Restore the existing backup
Restore your iPhone, iPad, or iPod touch from a backup - Apple Support
3) Sign out of the old Apple ID and into the one you intend to use moving forward
4) Create a new backup using the new Apple ID
Using these steps will allow you to get all of the data from the old backup onto a new device and then create a new backup associated with the Apple ID you are planning to use.
Cheers.