createRegistrationAttachment
abstract suspend fun createRegistrationAttachment(input: CreateRegistrationAttachmentRequest = CreateRegistrationAttachmentRequest { }): CreateRegistrationAttachmentResponse
Create a new registration attachment to use for uploading a file or a URL to a file. The maximum file size is 500KB and valid file extensions are PDF, JPEG and PNG. For example, many sender ID registrations require a signed “letter of authorization” (LOA) to be submitted.
Use either AttachmentUrl or AttachmentBody to upload your attachment. If both are specified then an exception is returned.