No RCTConvert UIView function found

I am trying to allow a custom property to my bridged view. The property should be an element wrapped in a so like this:

<SheetView child={<View><Text>rawr</Text></View} />

However this is causing the error:

No +[RCTConvert UIView:] function found.

Here is a screenshot:

My SheetViewModule.m code is set like this:

#import "SheetViewModule.h"

@interface RCT_EXTERN_MODULE(SheetViewManager, RCTViewManager)

RCT_EXPORT_VIEW_PROPERTY(txt, NSString);
RCT_EXPORT_VIEW_PROPERTY(child, UIView);

@end

and SheetViewModule.h:

#import <React/RCTViewManager.h>

@interface SheetViewModule : RCTViewManager

@property (nonatomic, assign) NSString *txt;
@property (nonatomic, assign) UIView *child;

@end

May you please help me fix this error.

It seems they had the same error here - https://github.com/kayla-tech/react-native-card-io/issues/12 - but they never solved it, just removed it.

We also see that it is used as prop here by the official react-native Navigator component - https://github.com/facebook/react-native/blob/master/React/Views/RCTNavigator.h#L18