One of the hardest challenges a writer faces is staying motivated. Sure, you were excited when you had the idea for the story and you wrote the first draft in no time at all. But now, after all revision (and rejections) the story is stale and you want to move onto something else.
Or: you've been working on your novel for a year, no, two years now. You think it is ready, but you keep getting feedback that there are problems with it. Character A seems flat. You need some better description in chapter ten. The ending isn't quite right.
Or: you've sold a few stories or a novel and you don't know where to go from here.
What can I tell you except keep writing. This happens to all writers. Sometimes I skip a day or two on my novel or current project. I do that either to think about it some more or because to many other things distract me.
Distractions are rampant these things. Shall I tell you how many games I have in my phone that I play daily? But I need this time to rest and recharge.
And then there's the house, dogs, car, computers, wife, and my own personal health that all need attention. And all are important.
But none of that matters. Keep writing.
Some writers need inspiration to write. I certainly need a good idea or general notion of what I want to say or what the plot is before I sit down at the keyboard. But this isn't a requirement if you are just trying to keep your skill sharp. Free write. This is a technique to let the juices flow that I learned to college years ago and it works well.
How does it work? For a period of 15 to 30 minutes write about whatever comes into your mind. Don't edit it. Just write. If you think 30 minutes is too long, start with 15 minutes and add a minute or two each day. Before long you'll be writing for 30 minutes or more.
What you might find is that issues that you are unaware of are keeping your motivation at bay. You might be scared of success or failure or something else. You may have a personal issue that is sucking so much of your energy your motivation to write is gone. Or you may hit on an idea that will propel to your next big project.
So try it and see. And above all keep writing.