A family of Microsoft word processing software products for creating web, email, and print documents.
I'm using an iPad mini 4th gen with iOS 15.8.3. I'm not experiencing this problem. Both Print Layout and Mobile View look fine with the proper colors.
It sounds like you did all the things one would do. You might try rebooting the iPad. If that works, then do the same for the iPhone. You might also try using a different font on your PC and storing the document and retrying again on your iPad.
Sometimes an app falls behind when the iOS is updated, and may become partly incompatible, until the app is updated. Check the Apple store and see if there are any reviews from users who are experiencing the same issue.