Below is ssh client side log.
$ git fetch
debug1: Connecting to bitbucket.org [104.192.141.1] port 22.
debug1: Connection established.
debug1: identity file /c/Users/msun/.ssh/id_rsa type -1
debug1: identity file /c/Users/msun/.ssh/id_rsa-cert type -1
debug1: identity file /c/Users/msun/.ssh/id_ecdsa type -1
debug1: identity file /c/Users/msun/.ssh/id_ecdsa-cert type -1
debug1: identity file /c/Users/msun/.ssh/id_ecdsa_sk type -1
debug1: identity file /c/Users/msun/.ssh/id_ecdsa_sk-cert type -1
debug1: identity file /c/Users/msun/.ssh/id_ed25519 type 3
debug1: identity file /c/Users/msun/.ssh/id_ed25519-cert type -1
debug1: identity file /c/Users/msun/.ssh/id_ed25519_sk type -1
debug1: identity file /c/Users/msun/.ssh/id_ed25519_sk-cert type -1
debug1: identity file /c/Users/msun/.ssh/id_xmss type -1
debug1: identity file /c/Users/msun/.ssh/id_xmss-cert type -1
debug1: identity file /c/Users/msun/.ssh/id_dsa type -1
debug1: identity file /c/Users/msun/.ssh/id_dsa-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_9.3
debug1: Remote protocol version 2.0, remote software version conker_07fc110085 834526c7cefa
debug1: compat_banner: no match: conker_07fc110085 834526c7cefa
debug1: Authenticating to bitbucket.org:22 as 'git'
debug1: load_hostkeys: fopen /c/Users/msun/.ssh/known_hosts2: No such file or directory
debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts: No such file or directory
debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory
debug1: SSH2_MSG_KEXINIT sent
Connection reset by 104.192.141.1 port 22
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
I checked my ssh key is correct, and there is only one under personal settings.