So Biotin brought back your hair ?
Biotin doesn't bring back hair. It strengthens hair ....
You have hair follicles...roots you can say.
With time, these roots gets weaken and thus hair gets thinner.
As long as root exists, you can try to make hair density thicker.
Biotin alone won't do wonders....
You have to shift towards a healthy life style.... overall
Physical fitness - moderate level but daily
Mental well-being - to reduce stress
Balanced diet - which includes proper protein, probiotics and multi vitamins and minerals in sufficient quantity (includes biotin)
And, then comes hair care - proper serum, shampoo, hair massage and so on....
If you want then you can have finasteride tablet to block DHT....
But unless you will improve your physical and mental well-being, no medication or treat would work effectively