ברצינות,

make sure that Master Sync is ON

To enable Master Sync, just follow these simple steps:
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Pull the status bar from the top of the screen down using your two fingers.
Look for the quick selection icon for SYNC.
Tap the Sync icon and make sure it’s enabled (indicated by green color).

Disable Power Saving Mode
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Another feature you want to check is Power Saving Mode. If this feature is on, your accounts automatic sync option will be sacrificed in favor of giving you more battery life. This will effectively disable any sync options and other non-critical services so make sure to turn it off. By default, this feature is off but we don’t think it will hurt if you double-check it. Here’s how: