It doesn't need light 24/7, Some people have lights on 24/7 during veg, some use 18/6, some use 20/4. As long as the plant is getting more than 16 hours light it will remain in veg.
I personally think a night cycle in veg is needed, others will disagreee and some wont... I use 20 on / 4 off in veg and get excelent results, Most use 18/6 or 24/0 as your using now.