Error connect SHH "no supported authentication methods available (server sent publickey)"

Summary:

When I tried connect to one instance by Putty the first time, I had the error "no supported authentication methods available (server sent publickey)".

Content (required):

Yesterday I created one instance ARM (Ubuntu Minimal at Oracle Cloud). When I tried connect to this instance by Putty, I had the error "no supported authentication methods available (server sent publickey)". I terminated this instance and created another instance with the same features. I checked the public and private ssh key that it is ok. I tried connect to last instance and I have the error "no supported authentication methods available (server sent publickey)" again.