Eye which was operated at 6 yrs of age  is lazy    ( amblyopic) & having very less vision resulting in divergent squint again ,our eyes are straight because of vision keep them straight otherwise it will take its anatomical position which is divergent squint, if amblyopic eye is operated it hardly remain straight for five to ten yrs,you can go for resugeory with not much expectations ,with regards

Hello A. Yes,it can be operated twice. B. Kindly share photos of your eyes so that I may guide you better