How do I get NIE for Spain Visa appointment?

Can someone please guide me as to how to get NIE number for Spain Visa? I am specifically applying for Digital Nomad Visa and sent the email to emb.abudhabi.nac@maec.es as they mentioned in the page. Its been 7 days, and still no response. I called BLS and they said that you would need NIE for the appointment visa as well.

I tried calling the embassy and sent email as well, but no response as of yet. The call just cuts abruptly. What can I do since I am in Dubai? Anyone who might have been through the process, please let me know.