Are you asking about crowns? or crown crates. Your title suggests crates (which ESO+ has never received for free as part of their membership) but your post suggests crowns. You should receive 1500 crowns per month subscribed when you make your payment.
If by chance Zos has provided a special offer to entice former subscribers to subscribe again that would have been a limited time offer, not an ongoing reward. Otherwise you would have likely seen it in the information for renewing your subscription.