Hi it looks like it may have gotten too much sun on those leaves, new growth is more tender than old growth. The brown spot may be a bit of bacterial infection brought on by the sunburn. The yellow leaf above it, it looks like you could peel it, and it forms a kind of sheath on the cane? I would peel it down and see if the spot goes through underneath it to the cane, peel it carefully. Also you can pour some peroxide down into the roots, it may have gotten too much water. Dends like a lot of water, but like to dry out a bit before the next watering. I hope that makes sense. The cane itself looks fine. I am concerned that you might have mites, but some cinnamon spray once a week should take care of that. I would also cut the leaves that are yellow just below the yellow part (into the good part of the leaf) just to be on the safe side, and dust with cinnamon or spray with cinnamon spray. It's not even close to dying yet, just the sniffles
. Good luck!