Jonathan,
My wife is in sales, and I’ve watched her have to find the balance between making a sale, and trying to connect people to tools and innovations they actually need. Said differently, sales can be about connecting and mutually fulfilling needs, such as you making sales that are about the client, where their needs are met by your product or service. The other is more pushy, moving product, saving up for the toy, and whatnot. My wife has found that surrendering into the former produces a strong sense of fulfillment for her, and getting distracted by the he later produces the void.
If you’re already committed to the client needs, and not pushy or quota-ey, then perhaps your heart just wants to give even more. Consider charity work, being a mentor, or some other way of giving back to the world. My teacher said that generocity brings joy, and perhaps looking for ways to be generous would help.
Finally, its plausible that the void is some other need going unmet. Do you self nurture? Is your relationship to your partner/children/family secure and joyous? Do you spend time playing, having fun and laughing? Eat healthy? Sometime we think we have a big existential crisis in front of us, when all we need is more vitamin B, or whatnot.
With warmth,
Matt