1. Try to update frequently as you can. Even if you feel not in the mood to update. It's best to try to. Or give A/Ns to at least assure your not dead.

2. Decide if you want to finish the book or not. It's important because if you lost the inspiration to update the book. The option you have is to put it on Hiatus to hope that you will have inspiration or just complete it. It was hard. I've been there.

3. Read other fan fictions or try to relax, watch some YouTube videos, anime, and try to get ideas again.

4. Eat food. It's ultimate remedy to heal your mind -^-

5. Don't try to overthink. Don't feel your readers pressuring you to update. It's ok if your slow update. It's fine. We all procrastinate. I procrastinate a lot sometime. I don't know if it's different for you but try to relax.