Logging in via FTP (correction: SFTP) with user sympl - is it possible?

I am having trouble solving this too. I have set /etc/ssh/sshd_config and ssh_config to yes instead of no yet still have problems

If I try with putty it tells me to logon as admin instead or root then logs me off.

If I try with winscp, which I really want to do I can logon as admin but that errors with “Cannot initialise SFTP protocol. Is the host running an SFTP server?” and Received too large SFTP Packet when I us the sympl user

Been pulling my hair out on this all day, and I don’t have much to start with.

auth.log doesn’t tell me much

    Nov 15 19:07:45 ip-172-26-0-55 sshd[4051]: Accepted publickey for sympl from 94.x.x.x p

ort 53290 ssh2: RSA SHA256:+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Nov 15 19:07:45 ip-172-x-x-x sshd[4051]: pam_unix(sshd:session): session opened for user
sympl by (uid=0)
Nov 15 19:07:45 ip-172-x-x-x systemd-logind[687]: New session 103 of user sympl.
Nov 15 19:07:45 ip-172-x-x-x systemd: pam_unix(systemd-user:session): session opened for
user sympl by (uid=0)