Go to My profile → Security → Two-Factor Authentication. Click Enable 2FA.
1. Scan the QR code with your authenticator app (Google Authenticator, Authy, 1Password, Bitwarden, etc.)
2. Enter the 6-digit code shown by the app
3. Save the backup codes somewhere safe — you'll need them if you lose your phone
From now on, Senly asks for the 6-digit code in addition to your password at every login.