@Lollylanham - It is important to determine why it lost so many lower leaves. If that is not corrected, then you may lose even more leaves.
When indoors, your FLF must be located in front of an uncovered sunny window and the soil completely saturated as soon as the top surface soil feels dry. I suspect yours was either not getting enough light or was allowed to get too dry or both.
Pruning is a personal choice. Left unpruned, it will add new leaves at the top of the tall stem as well as to the base plants. New leaves are unlikely to grow on the bare portion of the stem. If you prune back the tall stem, you will probably (no guarantee!) get new leaf growth starting at the point where you make the pruning cut. Your choice.
