Regex not matching in release name

Sonarr version (exact version):
Mono version (if Sonarr is not running on Windows):
OS: Docker on Linux
Debug logs:
Description of issue: I have a preferred regex set in a release profile that applies to all shows and it doesn’t seem to match all instances of Dual Audio even though it matches some.

The regex I’m using is dual.?audio|multi.?audio

Regex101 shows it should work fine and it used to work fine but I’ve noticed recently that it isn’t catching every release with Dual Audio in the name.

It’s not catching that release because it can’t parse it into a series and episodes.