docs(account): update 2FA flow for new security settings UX

Enable and disable flows now go through the dedicated Security settings
page with password-confirmation dialogs. Drop SMS setup steps (TOTP-only
for new users) and replace the SMS/TOTP section with a deprecation note
for legacy users.

DX-1074

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: matt423

src/pages/docs/platform/account/2fa.mdx

@@ -6,39 +6,34 @@ redirect_from:
   - /docs/account/2fa
 ---
 
-Two-factor authentication (2FA) is an authentication process requiring users to utilize two different forms of verification. 2FA for your Ably account requires your password and a security token sent to your mobile phone.
+Two-factor authentication (2FA) is an authentication process requiring users to utilize two different forms of verification. 2FA for your Ably account requires your password and a time-based one-time password (TOTP) from an authenticator app.
 
 Access your [security settings](https://ably.com/users/settings/security) to configure two-factor authentication for your Ably account.
 
 ## Enable 2FA <a id="enable"/>
 
 To enable 2FA for your own user login:
 
-1. Log in to your account and select [Profile Settings](https://ably.com/users/edit) in your account.
-2. Toggle **Enable Two-Factor Authentication** under the **Two-factor authentication** section.
-    * Re-enter your password as prompted.
-3. Select your **Country**.
-4. Enter your **Phone number**
-5. Click **Next** to receive an SMS with a security token.
-6. Enter the security token and click **Verify security code**.
-7. Scan the QR code into an authenticator app such as Authy, or Google Authenticator.
-8. Store your recovery codes in a safe location.
+1. Log in to your [account](https://ably.com/accounts/any) and go to [Security](https://ably.com/users/settings/security).
+2. Click **Enable** on the **Two-factor authentication** card.
+3. Enter your password in the dialog to confirm.
+4. Scan the QR code into an authenticator app such as Google Authenticator or 1Password.
+5. Enter the generated code to verify.
+6. Store your recovery codes in a safe location.
 
 ### Disable 2FA <a id="disable"/>
 
 To disable 2FA for your own user login:
 
-1. Log in to your account and select [Profile Settings](https://ably.com/users/edit) in your account.
-2. Click the **Disable Two-Factor Authentication** button.
-    * Re-enter your password as prompted.
+1. Log in to your [account](https://ably.com/accounts/any) and go to [Security](https://ably.com/users/settings/security).
+2. Click **Disable** on the **Two-factor authentication** card.
+3. Enter your password in the dialog to confirm.
 
-### Change phone number <a id="phone"/>
+### SMS 2FA <a id="sms"/>
 
-Disable and re-enable 2FA in order to update your phone number.
-
-### SMS and TOTP 2FA <a id="sms"/>
-
-Disable and re-enable 2FA in order to switch between SMS 2FA and TOTP (time-based one-time password) 2FA.
+<Aside data-type='note'>
+SMS-based 2FA is deprecated. Users who previously enabled SMS 2FA remain supported, but new setups use TOTP.
+</Aside>
 
 ## Enforce 2FA for all users <a id="enforce"/>
 
@@ -50,14 +45,14 @@ The account owner must already have 2FA enabled for their own login before they
 
 To enforce 2FA for all users:
 
-1. Log in to your account and select [Profile Settings](https://ably.com/users/edit) in your account.
+1. Log in to your [account](https://ably.com/accounts/any) and go to the account [Security](https://ably.com/accounts/any/security) page.
 2. Toggle **Require Two-Factor Authentication for all account users** under the **Authentication Settings** section.
 3. **Save** the authentication settings.
 
 ### Remove 2FA requirement of all users <a id="remove"/>
 
 To remove the requirement for all users to authenticate with 2FA:
 
-1. Log in to your account and select [Profile Settings](https://ably.com/users/edit) in your account.
+1. Log in to your [account](https://ably.com/accounts/any) and go to the account [Security](https://ably.com/accounts/any/security) page.
 2. Toggle **Require Two-Factor Authentication for all account users** under the **Authentication Settings** section.
 3. **Save** the authentication settings.