If you mean that your upvote has a zero value, it means that your voting power is depleted when you reach between 70% amd 80% of your voting power and your resource credit (RC) is so low. Try to replenish your voting power to 100% which means do not upvote anyone within 24 hours so you have the full Voting power of 100%.

Below is where you see your data and you can check it at:
https://steemnow.com/@joanimortenson.