There may have occured a kind of tissue damage at while or post-operation phase sir. It would be quite helpful to make it checked by a specialist doctor again. It is pretty hard to respond your inquiry or find the actual problem unless it is examined physically.
According to the growth graphic, you will achieve 80%-90% growth in 12th months after the hair transplant. I suggest you to contact your doctor about your results.
Vitiligo and graft whitening are together. Skin cells and grafts root cells lack of melanin pigments. If you carry these grafts anywhere, melanin pigmentation deficiency will go on. So your hairline grafts include white and normal color grafts. Only white grafts makes your hairline white.