Hi Guys

I started growing my first avo tree two years ago and it was doing great until a couple of months ago. I left it in the sun for too long and it got sunburned. The leaves dropped but there were new ones on the way and they seem to be ok.

After a couple of weeks, these leaves started to drop too and the terminal node started turning black. Ever since no new leaves formed and it looks like the black is spreading down the stem.

Further down the stem there it looks like some leaves are forming but not developing fast. Quite slow to no development. I need some help on what to do here. Not sure what it is or what to do to help it. Prune it back and to where? I'm terrified of losing my first avo and need to save it!!

Please help

Pierre