The one you need to talk to is gardengal48 (PNW Z8/9). She's a nursery professional in your zone.

There are a few things she should know.

What kind of grass do you have?

What kind of fertilizer did you use? Do you still have the bag?

Have you used anything else, herbicides, insecticides, fungicides?

And she may want you to be more specific about your location to help understand the climate and soil. PNW helps, but which side of the Cascades, or are you on an island, or slope? Name the town and that should do it.

I am happy to offer whatever advice I can but dchall's comments on necessary info are right on point. It is also helpful to know how much you want to throw at the lawn re: making it look pristine. Or are you willing to tolerate something a little less than perfect :-)

btw, moss is pretty much a fact of life here - it grows year round. And many homeowners will tolerate its presence as it generally remains green in summer with little to no watering, while the lawn is dormant and more brown than green. It really does depend on what your aesthetic is.