r00tz0neanswered grow question a year ago 1. Install some fans, NOT directly hitting her, but to gently move her around. She will strengthen the stem to stabilize.
2. Lights might be moved a bit closer, so that she is not stretching for more.
3. Cover the long stem by adding some more growing medium.
4. Silica, maybe, never used it since above steps always solves the issue.
Whatever you do, do it slowly and gradually.
Have fun! 💪