Help Needed: iTunes won't sync music to my phone!

[PanAm-L1011]

Hi All,

I'm not sure the right place to post this, but I really need help. I just downgraded from iOS11 to 10.3 and now I can't sync music between my iTunes and my iPhone. I have tired everything and really don't know what to do. iTunes appears to be blowing right by Step 3 in the syncing process. Any help would be much appreciated.

Thank you.

 

[zorinlynx]

You need to restore from a backup you took before you upgraded to iOS 11.

There are likely other things broken too; you can't go "backwards" with iOS without restoring a backup made on that previous version.