Changes are you ticket is gone, but that depends very much on what exact type of ticket it was in the first place and what the specific fare rules were.
First of all, you have gotten a full rundown of the ticket rules when you booked the ticket (and you actually did agree to these rules). If you still have those, read them carefully.
There are generally three types of tickets
- Normal tickets: not refundable, change for a fee (or not at all)
- Flex tickets: not refundable, no fee for a change, but you still need to pay for any change in ticket price
- Refundable: you can cancel an get your money back.
Most tickets are "normal" tickets these days since the surcharge for flex and fully refundable tickets is prohibitively expensive and "fully refundable" is often not available at all.
The details matter here, so you really need to read the fine print. Example: Qatar currently offers "cancellation for a fee" even for their Economy Saver ticket, but the fee is larger than the ticket price, so this is worthless. Same for flex tickets: the price difference is often MUCH larger than the change fee, so it makes no sense to buy a flex ticket.
Normal and flex tickets do expire. Pre-Covid the was 9 month to a year from date of original travel, but could be different now (Qatar offers two years at the moment). For fully refundable tickets it really depends on the exact wording in the rules. If they expire, they are either forfeit or automatically refunded.