itunes wont update my iphone

“All the new updates” does not tell us anything when discussing iTunes on your Mac.

We need to know the iTunes version number, and your MacOS name and number. Your iTunes may well be too old to support the current iOS version.

You have also not told us what messages you see when you attempt the backup.

How much free space does your Mac have? It might be worth checking for malware with Malwarebytes. It would be useful to know if a backup to iCloud could be completed even if you prefer to use iTunes. It would also give you a fall back position if you actually had to restore and found the iTunes backup wouldn't work. Options are good.

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Will it backup to iCloud if it won't backup to iTunes? What is the error message when the backup to iTunes fails?

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Try If your iTunes backup couldn't be completed or you can't restore from a backup - Apple Support.

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