Error: 'No more than 1024 characters' while inviting the attendees in a meeting scheduler:

Cause:
The meeting scheduler user interface will automatically transform the newly added attendees to a list display, and the number of characters is limited to 1,024 in the Attendees field.

Solution:
To get the older invite attendees user interface prior to the site enhancement, contact your Webex Customer Success Manager and ask that they submit an Ops Request to disable the option for Simplified Alternate Host Selection for your site. Note that this setting cannot be disabled in standard site admin. For help, see: How Do I Get Help with Webex?