i'm getting sign_and_send_pubkey: signing failed for RSA "/Users/user/.ssh/id_krypton" from agent: agent refused operation

[00xkhaled]

user@localhost~/.ssh $ ssh root@[ip-address]

sign_and_send_pubkey: signing failed for RSA "/Users/user/.ssh/id_krypton" from agent: agent refused operation
no such identity: /Users/user/.ssh/id_ed25519: No such file or directory
no such identity: /Users/user/.ssh/id_ecdsa: No such file or directory
no such identity: /Users/user/.ssh/id_dsa: No such file or directory
root@ip: Permission denied (publickey).