Internal Server Error 500 when sharing folder

When running my code I can share a folder one or two times but then I receive the Internal Server Error 500 afterwards.

Creating the shared folder works:

client.sharing.shareFolder(path: pathName).response { launch, error in

            switch launch {

            case .complete(let launchData):

               let id = launchData.sharedFolderID

               -> Code for adding shared member called from here

             shareFolder(id: id)

            case .asyncJobId(let jobID):

                // Do my async things here

                }

            case .none:

                print("None")

            }

}

func shareFolder(id: String) {

let member = Sharing.AddMember(member: .email("my.test@email.com))

client.sharing.addFolderMember(sharedFolderId: id,

                                       members: [member],

                                       quiet: false,

                                       customMessage: "Welcome to EZfile!")

        .response { _, error in

            switch error {

            case .none:

               print("Success creating share")

            case .some(let wrapped):

                print("Sharing folder error: \(#function)", wrapped)

            }

        }

}

The folder is created (I see it in Dropbox) but the share does not work in 80% of the times. Which indicates that I am creating the client correctly.

What am I missing here?