Use an authenticator app or email code. You can manage this in your Roblox Security Settings Never Share Your Cookie: Never copy-paste code into your browser or share your .ROBLOSECURITY cookie with anyone, even "friends" or "support." Use a Unique Password: Ensure your Roblox password is not used anywhere else.
Modern platforms like Roblox use several layers of defense that prevent automated software from guessing passwords: Rate Limiting Roblox Password Cracker Software
If you have lost access to your account, do not use third-party "crackers." Use the official Roblox tools: Use an authenticator app or email code