Moss is an indication of poor drainage, poor soil conditions and usually not enough sun. It is difficult to offer sound advice without knowing where you are located, the type of grass, and the amount of sun the area gets. If it is a shady area, consider enlarging the bed and plant some shade loving plants in front of the existing. Also if it is too shady, you can consider changing the grass to a more shade tolerant species. You could also limb up any existing tree branches to allow for more sunlight. Hope this helps

Thank you for the reply. Yes that part of the garden is a little shaded at certain times of the day and do intend to cut back the hedge to let in more light.. The new seed is shade friendly, but my question was more about scarifying more than once. I filled a green wheelie bin full of thatch and there is still a large amount left. Can I redo the process with an electric machine until it is all removed or should I let the lawn recover now until I do it again...

Also I think the drainage is good, but the lawn has been neglected for many years by previous owners.

Andrew we need to know where you live to help you. Also what is your watering schedule? How often and for how long do you water?

I am in the UK

UK is a start. Castle of Mey or Lizard Point? And watering?