You can edit the Descriptor Name, or Purchase Description, when setting up your payout method and directly from your Tickets tab. This description is what shows up on your guests' billing statements!
From your Tickets tab, select Payouts. Once in the Payouts menu, select Edit next to the current Descriptor Name and make the change you need. Keep in mind that, by default, the Descriptor Name will automatically be the event title until you change it!
If you are using Stripe as your payout method, you can also set your statement descriptor directly from Stripe! However, the statement descriptor from Splash will always override what you have set in Stripe, so be sure to make the needed changes in Splash following the steps above.
It is important to note that Descriptor Names can not include any non-alphabetic or non-numeric special characters such as (,$,&,#, etc.