TNC Group interview questions

i am a blockchain developer and they have vacancy for it, but i applied for both blockchain and backed developer because am familiar with both of them. i got interview for nodejs position and i performed well and they asked certificate attestation kind of things for visa processing. after 2 step of interviews there is no response from them, if am not selected why don't they email me with reason of not selected, at least they need to inform 'you are not selected'. I think they are not respecting developers