If you look very carefully inside the damaged flowers, you may find some tiny white worm like creatures. These are no more than 2 mm long so not easy to see. If you find them then you have Hemerocallis gall mites. There is , sadly, no cure. I know, we have them. Two choices, dig out the plants and burn them. Or. Remove every single flower on the affected plants and bin/burn. You may well need to do this for a couple of years to clear the infection and even then there is no guarantee. Sad really.

Hi Owdboggy , yep just looked and found the mites. Will it affect other hemerocallis I have planted near the 2 that have got the bugs? I must have had them last year too as they never opened .

Sadly, eventually it will spread to all of them. Supposedly it is only the early flowering ones which get it, but we have found it in all ours except the species.
Sorry!

early flowering ones tend to suffer more than the later varieties. also second flushes are not affected. I theink the adults are on the wing late May so plants are affected june.
certainly I remove deformed buds and then later ones are fine.

Lucky you Seaburngirl, all of ours are affected and all the flowers on some of the plants.