Quick question about thyroid result

[melcul]

Hi,
Male 30 with HBV,
I used Interferon Alpha for 2 months prior to Covid in March 2020, after quarantine started, the doctor took me off interferon because my WBC were going down, and I started Tenofovir which I've been taking for the past year.
I've been under a lot of stress and little sleep due to overworking myself on my job.
My hair thinned out a lot around 2,3 months after stopping the 8 Weeks Interferon Injections that I had.
Fair to say that the Covid situation made it extremely worse.
My doctor tested me for different vitamins and whatever they need to check why the hair was falling. (it stopped falling now, but it's still thin and I'm missing like 40% overall.
Everything came back ok besides a possible hypothyroidism.
All I could understand was that my TSH was around 6.3, from what I understand it should be in the range of , (<4.5,5)
I will have to check it again in 3 months time.
Is this by any chance revesible, or once the results are out of range, it stays that way?
Prior to this test, the tsh result was normal the doctor said.