Connect To What's Meaningful
Happiness at work is one thing, but meaning is on a completely different (and necessary) level. Happiness won’t sustain you through the more challenging and trying moments at work, but meaning will. Meaning gives deep motivation that keeps you going during stressful times.
Meaning is tied to a positive impact in the work you do (over both the short and long-term). Note the positive impacts of your work; from helping out a colleague (seeing their smile) to supporting the specific business needs of your organization, make a list of your impact and keep adding to it over time.
Connecting to how your work is meaningful (to yourself and others) supports feeling the joy in your work.