As we are on the borders of the brick pits (therefore on the edge of massive clay deposits), our grass has always suffered.
Tried aerating with a fork...probably not often enough to make any difference, my failure.
Relaid the lawn maybe 4 years ago, its as bad now, if not worse.
As said up post, if you don't treat the cause.....
I've considered digging down several feet and creating a soakaway with gravel...but the clay could be 10 ft deep, i just don't know.
So i've adopted the approach of its green, so that'll have to do. I'm not a gardener so am not a shining example or really have any substantial advice to offer