Try these:
General Download issues
Please refer to this article for Origin and Connection issues: Origin Errors and Connection Issues FAQ
The most common Download issues are as following.
Download doesn't start
Download is really slow despite of fast Internet connection
This is usually the case if there's lots of people downloading at the same time. You can try pausing the download and resuming to see if it picks up in speed.
Download reverts to lower percentage
Try turning on Safe Downloading in your Origin Options (click on the spoiler below to view an examplary screenshot).
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