Mayonaka Punch is an original anime story, so let’s say Aya last performed 2 years ago from the present, i.e. in 2022

The wider looking person in the video, whom I assume is the bartender who Fu meets, looked much younger in the video, so Aya probably had something of multi-decade a singing career.

It doesn’t say whether she was a superstar (unlikely), or an itinerant singer who sang in bars part time, or something in between, but there’s no reason to think that Aya gave up singing until whatever caused her death caused her to do so.