Can i change Bus Éireann tocket?

Does anyone know if I can change bus ticket of Bus Éireann?
I booked ticket online but i made mistake as below ;_;

(Booking i made) departure 27th Aug
(Booking I should have made) departure 26th Aug

Unfortuately i will leave Ireland soon so i closed account already so It is really not easy and do not want to get refund.
Actural departure date is even earlier than the date i booked mistakely. So i hope i can change my ticket. Do anyone know if i can change ticket ? Please let me know ASAP ;_;