Hello! I received this plumeria tree from a nice customer of mine. I'm not sure how to take care of it but I have it on my balcony and it gets a lot of sun. He did tell me that he didn't know what was causing these brown spots on the leaves and why some of the leaves are curling. I also noticed brown spots on the bottom of each stem of the leaves that are growing out. I hope you can see them in this picture. I'm not sure what to do or how to treat it but I do want to grow this tree so any help would be greatly appreciated. thank you!