Moving the plant to more light may make it not lean any farther in the
future, but it will not make any long, bare stem already present go
away. If the plant has sentimental value, root a leaf or two and start
yourself some clones. Leaves from the center of the plant work best,
rather than lower leaves. Snipa leaf, dust the end with rooting
powder, pot in moist medium, drape a plastic bag over the pot. Keep
moist but not soggy. Be patient. In time a new crown will form.

M. Reed