It's very likely caused by OpenSSH 8.8 potentially-incompatible changes:
Incompatibility is more likely when connecting to older SSH
implementations that have not been upgraded or have not closely tracked
improvements in the SSH protocol. For these cases, it may be necessary
to selectively re-enable RSA/SHA1 to allow connection and/or user
authentication via the HostkeyAlgorithms and PubkeyAcceptedAlgorithms
options.
Please try set HostkeyAlgorithms to +ssh-rsa and PubkeyAcceptedAlgorithms to +ssh-rsa in advanced options in Settings of the profile.
If you still face this issue, please set Log Level to DEBUG3 and send me a copy of desensitized connection log.
Kindly Regards,
Yang