Still no Naad
When naad returns work on learning to locate it. When it returns and you are situated in it, practice to detune from it and then tune into it repeatedly. You must learn how to find it because it is always there. Right now you are reliant on it finding you or being present where you are existentially located, but you can change this by learning how to find it. Then when you lose it, it will be a matter of going to its address only.