some iCloud data isn't syncing

Fixed for me. I also had this problem, with the message "Some iCloud data isn't syncing, etc.......Verify your account information to resume syncing" I clicked on the "resume syncing" link, got the spinning ball and then nothing. I noticed others on this thread had "reset" the phone with mixed results. I was trying to Verify my Account, so went to Settings, then clicked on my name, went to the bottom and clicked "sign out". The system logged me out of iCloud. I then signed back in, the error message disappeared and I now have access to all iCloud data. So glad I didn't have to spend hours on the phone with tech support.

I came across the same issue after setting up a new iPhone 15 Pro and migrating iCloud data from iPhone 13 Pro both running latest iOS. Even had the same issue when we tried a different iPhone 15 Pro. Problem was solved when we restored the eSIM (i.e., the phone number) back to the old phone, but left the new phone connected to wifi and my iCloud account. We were then able to click the button to resume the sync and it did it very quickly as was really only the Keychain data. Then we moved the phone number again to the new phone. All working great now.

I’ve just had this problem and what fixed it for me was going back to settings on my old phone, where iCloud updates were being blocked because I had to accept the new terms and conditions. As soon as I did that I was able to get past the recurring messages and complete the sync.

I have had the same issue with an iPhone 13. I took it to the Apple Store where their Tech and Genius gurus shrugged their shoulders and said 'It's a software problem' and that a factory reset is the only answer. This advice proved incorrect. To me it seemed illogical, so I did not do a full factory reset as I wanted to keep my data.

The solution proved simple but a little time consuming. The following steps solved my problem.

1. Get all your Apple devices (phones, iPads, Mac's, iPods, Apple Watch, anything that uses iCloud
2. Run updates on every device to the latest version the device will hold.
3. Using a browser, log into iCloud on each device (on the web, not via the app/os.)
4. Using the app/os iCloud connection, sign out of iCloud on each device (keeping the browser connection active)
5. Sign back into iCloud using the app/os on each device
6. Run backup to iCloud on each device
7. Remember - 'Each Device'

This worked for me. Everything synched, everything backed up, no errors, no data loss.

This is the first time I have ever posted anything but having gone through trying to get help and getting nothing from anyone, I wanted to spare someone else the pain and 'data-loss anxiety' that I know you can get when tech seems to fall apart.

Have a nice day.

I was able to fix this by agreeing to the new term and services of Apple on the old phone. This was just in the main settings page. Once the terms and services were agreed to both phones were able to access ICloud and this error message went away.

Hope this helps.

I bought an iPhone 15 Pro yesterday and I got this issue! I’ve tried all the steps mentioned in this thread and all didn’t work.

Last thing I tried was I backed up my previous phone (13 pro). Then I erased new phone (15 pro) so I could start setting it up again, then set it up from the back up I created from the 13 pro.

At first I thought it didn’t work, so I slept. I woke up and the Resume sync issue is still there. I checked the old phone and noticed it now has the issue and its Passwords and Keychain is off so I turned it back on and tapped resume sync.

I went back to the new phone and did the same and I was finally able to turn on Passwords and Keychain and it’s now syncing.

Also, the passwords didn’t appear right away. But it finally worked!

I went back to this thread to share this immediately because I know how frustrating this is!

I had the same issue after downgrading from iPhone 12 to 11 (long story :)), "some iCloud data isn't syncing". I set up both devices with the same 6-digit passcode, but the new device kept asking me to enter the code for “your other iPhone”. After entering the (same) code I could get a pop-up "not the code for this iPhone, but for your other iPhone", although the codes were the same.

It turned out that I had another iPhone 4S still active and it had a 4-digit code. Luckily, I still had the access to my old 4s, changed its passcode to a 6-digit code, went back to my new device, entered the new 4S code when I was asked for “another iPhone code” and voila - problem solved.

My advice is, check all your device, not only the recent one that you are replacing with a new one.

This work for me, I delete the backups from old devices I didn't have anymore on the iCloud Backup Area (settings/Apple ID/iCloud/iCloud Backup/ALL DEVICE BACKUPS)

Even after removing the device from the settings months ago, Apple still kept a copy of those old phone (Backups)

I had the same problem exactly and every time I tapped resume sync and put in my passcode it sent me right back to the "some iCloud data isn't syncing" page. I had help from an advisor (which is probably ai) and it didn't help so I turned off my passcode and then as long as you have another apple device connected to your account (for example a mac or iPad) you'll be able to use your mac or iPad passcode instead which will work (at least in my case it did). I've seen this happen multiple times before and this does work.

Sign out and then back into your Apple ID. This removed the notification for me.

I had same issues and some how I managed to remove that message I went into

settings - iCloud - turned on passwords and key chain

message disappeared

I did a iCloud backup before I did this

hope this helps

I think I had the same problem. Did you try my suggestion above and sign out of iCloud on your phone and then sign in again. That seemed to solve the problem for me.