38 year old Rubber tree dying
HELP! I have a 38 year old rubber tree, my father gave us when we married. Stretched out it is currently about 8 feet tall. I have successfully air-layered it two times(couple of years ago). We have lived in Raleigh NC for 25 years, and every spring we move it to our upstairs porch ( unscreened) where it faces west & receives very good light thru trees. In the winter it lives in front of the west window and tolerates poorer light.
It has become very ill the past couple of months, losing more and more leaves.It is now droopy, very few leaves at the ends of branches. the greener branches feel and look soft and wrinkly. The darker "barkier" branches are not hard and one shoot has peeling bark on the lower plant. In desperation, we repotted with new soil in the same pot (12 inch) two weeks ago and the root system looks good but not extensive as I would have imagined.I do not over water and I fertizer monthly. recently I have applied the oil spray "Volick".
A number of years ago, I worked at a premier garden center in Raleigh for 5 years ( Logan's Trading Co.) and I have a fair knowledge of plants. I have no answers this time.
I hope you can help me; this plant is a part of me and has traveled the country with us thru our married when my husband was transferred with his job. I have given my 2 grown children the air-layered starts when they married and bought their own homes.
I don't know what to do.