Frontal hairs that don’t grow

Question for you. I am 41 years old. Been on Finasteride for four months. From the tip of my hairline to about 3 inches back has miniaturized slightly. I have noticed that it no longer grows in length. Is this common? I have to buzz cut the rest of my head to match that front part every few weeks. What could be the reason for this? Why don’t those follicles grow anymore…it is like they...

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