In case of pausing syncing with icloud, the synchronization of iPhone could be temporarily stopped due to the low battery, low power mode, poor internet connection, lack of storage in iCloud, or other reasons. First, try connecting your iPhone to the internet Wi-Fi network and charging it for a while to let synchronization work again. You can check the amount of storage in iCloud in the following way: Settings -> Your Name -> iCloud. Another solution is to restart your iPhone and make sure iOS is updated. It is better not to change iCloud settings many times if there are some important things left to synchronize.
Read more – https://datarecovee.com/knowledge-base/syncing-with-icloud-paused/