After 10 hours also feeling sleepy tired

Dear sir Every day I am sleeping  8- 10 hours. after wake up feeling sleepy tiredness low energy. In Sleeping in dreams I am groaning 20 sec unable to move and speak then I wake up. It will happen every month 2 times.  I used clonozepam 0.25 mg for 20 days but problem is not solved. After doing small work feeling tired sleepy. After wake up not feeling refreshing. Due to this unable concentrate my work.  This  problem from  last 6 years. So many doctors are consulted but problem not solved. My blood test, sugar test, thyroid test are normal. I already used vitamin D and calcium tablets for 2 months  but problem not solved. My MRI and EEG test also Normal.I am not over weight and I don't have  snoring. Kindly suggest permanent solution