We need to ask this question often.
If the answer is no, then you need to dig deeper.
Why are you not having fun?
Is it because you have not updated your skills or faced a new challenge in a long time? If yes, then work to improve your skills and seek new challenges.
Or, is it because the parts of what you do are boring?
Being an entrepreneur is fun because of growth, learning, and excitement. But it has non-fun parts like dealing with employees and having tough conversations with customers. In such a scenario, you can reduce the non-fun parts by hiring some to do it for you.
If this does not work you can embrace a new identity. Like from being someone who executed plans for people, you can become an advisor.
You can also change your identity, within the same field, or move to a totally new field. I am sure in case of the move, there will be bigger challenges but the fun will also be more.
So, ask yourself:
Am I having fun?
Am I growing?
And, don’t stop seeking fun and growth until you get them.