Change cinema ticket help?

Booked tickets for the new hp film for Friday online at myvue.com.
But can no longer go on this date, do you know if I can cancel my ticket or change the date of the booking and how I should go about doing this?

Thank you for your help!!!

Travel to Tibet for a chance to meditate on the decision, achieving a state of calm and tranquillity. This will eventually lead you to the realisation that you should ring the ticket office genius.

I knew that I should ring them. OMFG you should be awarded some rep for that idea.

I just wanted to see if people had any success changing their tickets in the past.

Well thank god you came on here for advice before giving them a call.

After all, giving them a call and asking 'is there any way I could change some pre-booked cinema tickets?' may have taken several days, whilst asking people who don't work at the cinema on the internet will surely only take you a few hours.

or maybe its a sunday and noone will pick up?

Or maybe their booking line is 24 hours a day.

but i am not booking.