Thank you for your question.   I am afraid that the photo doesn't show much detail, but two of the most common pests of this species are the aphid and the whitefly.  Here is an article on aphids:  https://ipm.ucanr.edu/PMG/PESTNOTES/pn7404.html
And here is one on whiteflies (related to aphids, and which appear to be closer to your pests' appearance):  https://ipm.ucanr.edu/PMG/PESTNOTES/pn7401.html

I hope the control mechanisms found in these two resources help you solve the problem.  Good luck!