We are often hard on ourselves for not being "motivated"...
But have you ever considered that motivation isn't always in your immediate control.
The best example I can give you is gut health; if your gut is suffering, so will your mood, your productivity, your anxiety, and your motivation.
When I had severe IBS, there was NOTHING I could do in the moment to change these things, it was physiological, and until I fixed my gut health they continued to suffer.
If you want to develop more "motivation", try focusing on how you treat your mind and body.
Exercise, nutrition, mindfulness, rest, socialising, fresh air, organising your environment, surrounding yourself with positivity...
These simple practices will make a world of difference.
It's also essential to keep on top of your wider health. Issues in the gut can fly under the radar with no symptoms, as can many other issues in the body.
Don't take what seems like "good health" on the surface for granted, take care of yourself from the inside out.