Your primary event link will always have the format:
This URL (link) is based on the original title and date used when the event was created. You cannot change the primary link once the event is created. You can add any variety of other links that will send users to the ticketing page. However, once the ticketing page loads, the address bar will always show the primary link.
Please note that the majority of users will never look at the address in their browser, but rather the info on the ticket page. Also, in mobile browser, only the first part of the link is visible. If you are adamant that the link must appear particular way when loaded in a browser then you are able to delete your event and resubmit it with the title and date you would like to have in the event link.
To add new URLs (links) for your event, click to expand the URLs section, and then click on the "+" icon to create a new link that you can share with your potential attendees.