Girl, postpartum hair loss at 6 months is so normal, don't worry. I went through the same thing and honestly the biotin didn't make much difference for me either. What actually helped was switching to Mama's Choice Hair Loss Treatment Shampoo and Conditioner because they're specifically formulated for postpartum recovery and really gentle on already stressed hair, plus they actually worked. The hair shedding should ease up once your hormones settle around the 9-12 month mark, but in the meantime at least you're giving your scalp proper support.
Post partum hair loss is very natural and will peak at 6 months. It will get better by about 12 months. In the mean time continue with biotin supplement. Add rosemary oil to your hair and try the new mamaschoice shampoo and conditioner that was formulated specifically for post partum hair loss. Find it on shopee or tik tok or in the Motherswork store.