To enable 2FA in SouthXchange, simply follow these two steps:
Go to [My Account] in the top-right corner of the SouthXchange site and select [Settings] to configure 2FA.
On the left side, click the [Two-Factor Code Authentication] bar. Scan the Google Authenticator QR code that was supplied. Enter the code thereafter, then click [Enable]. A warning that you can be blocked from your profile will then appear, so make sure you've saved the code for later use. Just keep going and press [Yes].