Our beloved Yucca plant has been dropping its branches quite a bit, the leaves seem ok but the branches that were fully upright now becoming almost horizontal, stem feels like hollow towards the tips. A few months ago we had fungus gnats problem and we drained the plant for a few months then applied a bit of soapy water, neem oil solution. Fungus gnats seem to be gone and it was happy but last few weeks this started to happen. Do you recognise why this happens? Do we need to repot it? any guidance much appreciated.