When using landscape grass type the grass material starts to flicker.

Hello when using the landscape grass type the grass material starts to flicker I’ve tried other meshes with the material and work is only when applied to the grass landscape the flickering start I’ve up the screen size and it fixes the grass to an extent but still happens I’ve also tried different anti aliasing but it breaks the landscape. I have also tried just a base colour but it doesn’t fix the flickering. Also the version of unreal engine I’m using is ue5.02 and cannot upgrade.