Good Afternoon Blade_27,
I understand you are trying to get the music that is in your iTunes Library on your PC onto your new iPhone SE. Because you have had to switch to several iPhones, I think the best approach would be to set up your current iPhone as a "new" phone.
Instead of trying to restore from a backup, start fresh by syncing just the music and playlists that you want from your iTunes library to your iPhone.
Once that is done, you can enable iCloud on your iPhone and you will once again have access to your contacts, calendars, etc. Here are a few resources to get you started:
How to erase your iOS device and then set it up as a new device or restore it from backups
Erasing all content and settings will delete all of the data from your device, including songs, videos, contacts, photos, calendar information, and anything else. All device settings are restored to their factory condition.
To remove all settings and information from your device, tap Settings > General > Reset > Erase All Content and Settings.
If you can't erase your device, restore the device using iTunes.
After your device is erased, you should see the following screen:
Follow the steps to complete the setup assistant. When prompted, select "Set Up as New iPhone." Then tap Next.
Skip the Apple ID sign-in, in case the original issue was related to any of your content on iCloud.
After setting up as new, you will need to enter your Visual Voicemail password for iPhone (on carriers that support Visual Voicemail). If you've forgotten your password, contact your carrier to help you reset it.
After erasing and setting up as a new device, your device is now in a factory configuration. Re-try what you were trying when you first found the issue to determine if erasing and setting up as a new device resolved the issue. Content on the device might have caused the unexpected behavior.
- If the issue persists, you might want to contact Apple Support.
- If the issue is resolved, sync one type of content at a time back to your device. For example, if you had an issue playing music, add songs from iTunes and confirm that they will play. If your contacts weren't loading successfully, add the contacts back. After each sync, test to see if the issue has returned.
Sync your iPhone, iPad, or iPod touch with iTunes on your computer using USB
Take care,
