OurBus tickets cannot be changed, however you can cancel your original ticket and transfer the money to your OurBus Wallet. This credit will reflect in your Wallet immediately and you can use this to book another ticket on their website/app.
You can cancel by clicking on the "Cancel Ticket" button on your emailed ticket or by logging in to the OurBus website/app and finding the ticket under "My Passes", where you'll have the option to cancel.
If you do not have an account with OurBus, you can create one by going to their website: https://www.ourbus.com/ and clicking on Login and then entering your email and password in the Sign Up tab.
After you are logged in, you can go to "My Account" and click on "My Passes" to cancel your ticket:
Once canceled you will be offered a credit into your OurBus Wallet for the amount paid. Wallet credits can be used for your next purchase and have an expiration period of 5 years.
Note: OurBus Wallet is a form of payment that can be used on the OurBus platform (both web & app).
You can read more about OurBus Wallet here: https://www.ourbus.com/wallet