Definition of 'xxx' must be imported from module 'yyy' before it is required

For example, We have a pod 'Dependency3' declared Class A

@interface A : NSObject

- (void)test;

@end

pod 'Dependency1' declared Class B and a category of Class A

@interface B : NSObject

@property (nonatomic, copy) NSString *bText;

@end

@interface A (Dep1)

@property (nonatomic, copy) NSString *aTextDep1;

@end

pod 'Dependency2' declared categories of Class A and B

@interface A (Dep2)

@property (nonatomic, copy) NSString *aTextDep2;

@end

@interface B (Dep2)

- (NSString *)bTextDep2;

@end

And the dependency relations are no problem:

Dependency2 -> Dependency3 & Dependency1
Dependency1 -> Denpendency3

In podfile, we enable some of them's modular_headers

  pod 'Dependency1', :path => './Dependency1', :modular_headers => true
  pod 'Dependency2', :path => './Dependency2', :modular_headers => true
  pod 'Dependency3', :path => './Dependency3'

Now if you use class A and B in main project or in another new pod, compiler will tell you

Definition of 'A' must be imported from module 'Dependency1.A_Dep1' before it is required

This problem will sometimes disappeared after I cleaning build folder and module cache folder.

This simple example is simplified from my case which is found in a large component-based project with objc and swift code.

The most important things is why it happened, maybe the include order of module maps or others? I'd be appreciated if someone can help me.