Arrrgh! It's not working anymore!

S.P.! Y U NO WORK ANYMORE?

Before I could at least feel myself drifting off and its effects coming over me. But recently I would try to nap or be in bed and I wouldn't move... but nothing would happen. I would just feel heavy from not moving for 15 minutes.

What should I be doing to get lucid?

is this right as you first go into bed? or in the middle of the night?

Napping is usually 3-4 o clock, trying for S.P. is either at 11-12 at night or when I wake up at around 3-4. I managed it twice in one night at that time, but now it just won't happen.