How can I solve this depency error in Nestjs - nestjs

Question

I can't find out, where my problem is. I get the following error:
Nest can't resolve dependencies of the BService (?, AService). Please
make sure that the argument at index [0] is available in the CModule
context.
I have 3 Modules, A, B, C.
C should be able to use services from B, and B should call services from A.
A and B have TypeOrm imports and an entity each.
Here is the code:
app.modules.ts:
#Module({
imports: [
TypeOrmModule.forRoot(),
CModule
]
})
export class AppModule {}
c.module.ts:
#Module({
imports: [BModule],
controllers: [CController],
providers: [BService]
})
export class CModule {}
b.module.ts:
#Module({
imports: [
AModule,
TypeOrmModule.forFeature([B], 'default')
],
providers: [BService],
exports: [AModule, BService]
})
b.entity.ts:
#Entity()
export class B {
#PrimaryGeneratedColumn()
id: number;
#Column()
name: string;
}
b.service.ts:
#Injectable()
export class BService {
constructor(
#InjectRepository(B, 'default')
private readonly bRepository: Repository<B>,
private readonly aService: AService
) {}
}
a.module.ts:
#Module({
imports: [
TypeOrmModule.forFeature([A], 'default')
],
providers: [AService],
exports: [AService]
})
export class AModule {}
a.entity.ts:
#Entity()
export class A {
#PrimaryGeneratedColumn()
id: number;
#Column()
name: string;
}
a.service.ts:
#Injectable()
export class AService {
constructor(
#InjectRepository(A, 'default')
private readonly aRepository: Repository<A>) {
}
}

Answer 1

In your CModule you do not need to define providers: [BModule] as you will overwrite the value given from BModule. As BModule already exports BService you shouldn't need to do anything other than import BModule into your CModule then you can use BService with no problems.
Side remark: is there any reason you have dependencies across your modules? Most of the time if you can keep from importing other modules if it isn't necessary it'll make a lot of your code easier to work with.