Cancelled flight, how to redeem voucher.

I cancelled my American Flight today and they told me I am able to use the money from my original ticket towards a new ticket. The customer service agent was very brief and told me my flight reservation has been cancelled then gave some mumbled instructions on how to proceed. I was expecting an email with more information to follow but I haven't received one and my original ticket is no longer showing in my account. Any advice? I can't get in contact with another customer service agent because they're getting too many calls right now.

Basically just wondering how I can use the money from my original ticket for a new ticket now that the original is cancelled.