Depending on size a sports bra can work - some people wear two at the same time but that's not something you should do all day. Bandages seem to be very dangerous, especially when you're chest is a bit on the larger side so that's not a good idea. Also, I found this site that has a few options I didn't even know so hopefully you'll find something that works for you there:
https://www.minus18.org.au/articles/how-to-bind-your-chest-safely-and-healthily
Best of luck with these and be safe! ♥️