UE 4.27.2 interior static lighting quality good on Android but very bad on iOS

Hello all, I have been pulling my hair out on this and hope someone can help.

I am developing an interior game for both Android and iOS. Everything is set up and the project packages for both operating systems successfully. The lighting quality on Android is as expected - high resolution, smooth and good quality. However, when packaging for iOS, even though packaging successfully, the lighting always comes out at what appears to be very low resolution, blotchy, full of artifacts and low quality. I have tried everything including building on production quality, messing with the static mesh and world lightmass settings, deleting various folders and rebuilding and verifying the new version of UE 4.27.2, but nothing seems to work. I can not get the lighting on any iOS build to be the same high quality as on Android.

Can somebody give me a solution? Thank you in advance for your help.

Hey, does anyone have any advice on this? Thank you.