Why won't my milk dry up completely

Has this happened to any other moms out their....

I stop breastfeeding when my was 4 months old. Took about a month but I got to the point where I didn't have to pump and my breast were slowly drying up. In the beginning I noticed I still has small amounts of milk in each breast but nothing that my me uncomfortable or have to pump. I thought my breast would just fully dry out with Time....

My daughter is now 7 months and I still Have small drips of milk if I squeeze my nipple. When will this no longer happen

How this happen to anyone else