Q.falling over yucca
Why does my yucca get so tall and fall over? What can I do about this?
You can try to straighten the plants. Take a rope with a short length of garden hose strung on it and loop that around the tree. Use the garden hose to make sure the plant does not get damaged by the rope. Using the rope, pull the plant just a bit in the direction you want it to go and stake the rope down in the ground. Every few weeks, tighten the rope until the plant is standing straight again.
Pruning it back may also help if it is becoming too top heavy. Here is more information: https://www.gardeningknowhow.com/ornamental/foliage/yucca/yucca-plants-care-and-pruning-tips-for-pruning-a-yucca.htm