iOS 18: Web app only using low quality voices

Just upgraded to iOS 18. Now on the Clozemaster web page, the option to use Clozemaster voices is gone. It reverts to use “random” voice, and the only available voices are the low quality “eloquence” (ie comical) voices. In the voice select dropdown menu, it doesn’t show any of the standard voices that have enhanced and premium versions even though I have them installed.