Hello,lydianicoleeee,I think you can use iStonsoft iPhone to Mac Transfer to transfer iphone music to itunes library,this is a good method to copy music from iphone to itunes,you only need these steps to move songs from iphone to itunes library
Step 1: Connect iPhone and Computer
Connect your iPhone to Computer through usb data cable,Download and run iStonsoft iPhone to Mac Transfer tools.
Step 2: Copy iPhone music to new Computer
View your iPhone music,Select you want to transfer music from iPhone to iTunes library,and check it,Click "Export" to start transferring music from iPhone to compute
Step 3: Sync music from computer to iTunes library
Run iTunes,and then simply drag the music exported in Step 2 into iTunes direclty. this is very easy to Sync the expoted music from computer to iTunes library,Finally you will success to copy music from iphone to itunes
library
Believe you can transfer iphone music to itunes library and success,Finally,Wish you : Merry Christmas!
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