Moire pattern created by Photoshop

I have some great shots of a twilight and night storm two night ago. When post processed in LR they look great but started to show some "moire" that looks like a waffle pattern mainly on the clouds and empty sky, tghis got even worse when opned in PS, there it really show. As far as I can tell moire or other kind of patterns only occur when shooting things with a ppatern like fabrics. Has anyone experience this? I am shooting Canon eos R with 24-105 lens.