Honestly, it's difficult to reproduce a bug like this with little info. If you have screenshots of that situation happening (with a sequence, like show the match history and where the seeds should have been added), it could help us find out where the problem lies.
Browse forums
Ankama Trackers
Seed storage sometimes bugged
By OrehRuoy#7151 February 28, 2018, 05:03:04
AnkaTracker
Say your seed storage is empty and you use bramble to kill a minion thus getting 1 seed. It will show it but sometimes it won't let you cast it even if you have enough ap
First Ankama intervention

Respond to this thread
Honestly, it's difficult to reproduce a bug like this with little info. If you have screenshots of that situation happening (with a sequence, like show the match history and where the seeds should have been added), it could help us find out where the problem lies.
This happens to me too!
I cant say what causes it, just now it happened, it was after I had used "Bramble" on an enemy without killing it (so I did not get a seed), but I'm not sure if that is the trigger for this. I could cast seeds the next turn(, but it's really frustrating, as I could not cast a seed to trigger "first strike" on the first strike sadida man who gets frist strike when you plant a seed. First strike. Let me say it one more time since it sounds cool! first strike dude who gets first strike when you cast a seed).
So, let me summarize this:
Am I getting everything right?
Not entirely, I had 5 seeds in my reserve. Use bramble on a minion, I don't kill it (so I dont get a seed), and when I tried to place seed the same round, it did not work. Though again, I'm not sure if that was the trigger.