As per the documentation there is no value called ‘web’ its one of these
‘ios’ | ‘android’ | ‘native’ | ‘default’
So you have two options
Either to use {Platform.OS === ‘default’ ? and use it as web or do the other way {Platform.OS === ‘ios’ || Platform.OS === ‘android’ and render the mobile Modal
You current issue of the white screen is because all 3 scenarios opens the mobile modal
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