It's hard to pinpoint exact reasons, but it could come down to the receptors in your brain being somewhat burned out from overstimulation. For example, if you have been using the computer or phone for a lengthy period of time during the night, or if you have been overconsuming dopamine or serotonin-boosting foods or drugs like coffee or spicy noodles. There are a few ways to address this. Obvious choices include things like a dopamine detox and a ketogenic diet. Other systematic approaches could include changing your circadian rhythm to its natural state, watching the sunrise and sunset, and doing cold exposure.
Beyond this, i can only recommend that you Study and practies Sri krisna and leave this material life to become a devotee. I do recommend the andrew huberman podcast episode about dopamin, I also would recommend that you start a protocole to max out your testo if you are a man.
May love and life be abundante to you.