Low PM cortisol

Just received my blood test results and

Cortisol Levels • AM Cortisol: 500 nmol/L (Range: 145–600) • PM Cortisol: 75 nmol/L (Range: 95–462)

I’ve had insomnia for 4 months, low energy, muscle and joint pain.

Add to this, low testosterone, estradiol and shbg.

My question regards more around the low PM cortisol and if it’s that causing the insomnia? My blood test was taken at 4 PM.