There is such a massive gap in difficulty between the dumbbell shoulder press and the dumbbell bench. Dumbbell shoulder press is borderline impossible to progress on.
My Barbell overhead press max is like 195-200 so my db shoulder press should be higher
I use small increments progressively and track my lifts, even if its 1.5lbs its still an increase.
What also helps for me is reverse pyramid, after some light warms up, usually 50% of my mix lift, my 1st working set is my max and for about 4-6 reps, then a good 3 min rest then progressively go down in weight.
That has helped me so much, If you lift heavy, your muscles have no option but to grow