The server may inform the client of errors that prevented public key authentication from succeeding after authentication completes using a different method. These may be viewed by increasing the
LogLevel to
DEBUG or higher (e.g. by using the
-v flag).
reference:
https://man7.org/linux/man-pages/man1/ssh.1.html
LogLevel - Gives the verbosity level that is used when logging messages from ssh(1). The possible values are: QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3. The default is INFO. DEBUG and DEBUG1 are equivalent. DEBUG2 and DEBUG3 each specify higher levels of verbose output.
reference:
https://www.man7.org/linux/man-pages/man5/ssh_config.5.html
You may also refer to WikiBooks for more information on logging and troubleshooting, specific to OpenSSH:
en.wikibooks.org
I hope this helps!