This time last year we had 2 foot of clay soil removed & replaced with new top soil and turf. Initially this was a luscious green sward which we kept watered throughout the hot summer. During the autumn it was a little patchy with some areas greener than others. Last week I noticed large rings had appeared over a large area of the new lawn. I understand this is a fungal infection and the only way to eradicate it is to replace 1ft of soil & re turf it. Should we expect the original contractor to do this again or is it just bad luck?