I bought this Agave at Gardenworks three months ago and it lost three leaves. The leaves always look okay and then one day the spines aren’t very spiky anymore if that makes sense. Then the leaves start shrivelling and turning orange and brown until they’re dead. I have this planted in cactus and succulent medium and it’s under a grow light. It has been doing so well since I got the light but I noticed one of the leaves is starting to shrivel. What am I doing wrong?