change vendor public ssh key for sftp again

In 2020 i posted same issue, and the solution was to
1. remove the entry from the /home/user/.ssh/known_hosts file
2. connect QSH ssh -T xxxxuser@xxxxxxxxxxxxx and accept
3. worked...

But this time i only get a "failed".
I did attempt to paste the key they sent me, but same error (although
wondering if requires any kind of "line feed").
Also message mentions a "fingerprint key", but assume that is their proof
to me.
Had only a 24 hr notice for this change.

Calling their support in case they have flagged this account for mult fails
- connects many times per day.

Thanks

Jim

@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
SHA256:+blahblahblah.
Please contact your system administrator.
Add correct host key in /home/XXXXUSER/.ssh/known_hosts to get rid of this
me
ssage.

Offending RSA key in /home/XXXXUSER/.ssh/known_hosts:1

RSA host key for sftp.usps.com has changed and you have requested strict
chec
king.

Host key verification failed.

Press ENTER to end terminal session.