Like any scar on the skin after an injury
,this lung scar will also remain permanent.
There is no treatment for this.
Get a CT chest done to see whether this lesion in lung is active or not.
If there us no active lesion,then there should not be any problem.
However,if CT shows the lesion to be active,then you have to go for full proper treatment of TB.
Your earlier treatment for 3 months was inadequate.