hight T and low Dht

I stopped propecia 1.5 years ago

I did blood test

my T is high

Testostérone 7.01 ng/mL (2.8-8.0)

but my DHT is low

DHT 0.56 ng/ml (0.33-1.20)

How can I explain that
If my T is high, my DHT should be also high because T is converted in DHT

is it because my body is producing very low 5-a-reductase?

any suggestion?

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