Based on your post and from the screenshots, you're on an Apple device. I'm not an Apple device user but I can give an educated guess on what's happening. Those restore purchase notifications show up whenever one of these events happen:
1. First time sync of a profile after a fresh install or reinstall
2. Clearing the data and/or cache of the app (PVZ2) which will then trigger a profile re-sync
If you're not doing any of those then it could be a device problem (probably a storage or memory issue). You may need to have your device serviced. As for why you're not receiving the pack, you may have already used it. The plant should still be in your roster but the seed packets can only be claimed at the time of purchase.
Hope this helps you.
