smtp EHLO missing auth extension

smtp EHLO missing auth extension

When transmitting an EHLO client.example.com, using:

        "scheme": "smtp",
        "host": "smtp.zoho.com",
        "port": 587

I get only two extensions:



The AUTH extension is missing, e.g. I thought it should be like:
"
S: 220 smtp.server.com Simple Mail Transfer Service Ready
C: EHLO client.example.com
S: 250-smtp.server.com Hello client.example.com
S: 250-SIZE 1000000
S: 250 AUTH LOGIN PLAIN CRAM-MD5

"
In my Mail client it possible to use the smtp settings with port 587 and authentication Password. But in swift I looks like it is missing and I can't do it that way.