My Iphone won't sync with my laptop?

I bought a new laptop recently and I've signed in on my iTunes account to the same account that my iPhone is. I've deactivated my old laptop and authorised my new one. It detects my phone and it says that it's syncing but it doesn't do anything, nothing changes on either device after it says 'finished sync'.

I'm a little confused as to why it's still not working and it's very frustrating not being able to put new music onto my phone which I already have. Any suggestions on how to solve this problem?

P.S with resetting my phone to it's factory settings, my only concern is losing numbers rather than music as most of it is on my laptop or I have it on CD

Thanks for reading, send a link to a question you want answering and I'll gladly help.

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