Since you have Joomla 4.2 you are no longer using Akeeba LoginGuard, you are using Joomla's built-in Multi-factor Authentication which is, indeed, based on LoginGuard (I contributed this code to the Joomla project last year).
LoginGuard for Joomla 4.2 is just a migration script and the two plugins (Code by Email and Code by PushBullet) I could not include in Joomla itself. The migration code runs automatically upon installing LoginGuard 7 on Joomla 4.2 and later, and simply transfers the configuration from LoginGuard to core Joomla and toggles the necessary plugins so you have a seamless transfer of functionality. Since both LoginGuard 6 and Joomla 4.2's MFA share 95% of the code it was trivial for me to do that in a way that it's completely transparent to you :) That is to say, there's not much, if anything, left of LoginGuard to disable.
The error message you get is very likely something coming from your template or whichever component you are using in the site's default (home) menu item and PHP 8.2.
Nicholas K. Dionysopoulos
Lead Developer and Director
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