Voice Isolation is not working on my iPhone 13 Pro with iOS 18.6.2

I have an iPhone 13 pro, recently bought one and it's updated to ios 18.6.2, so the problem is that voice isolation is not working on any thing whether it be facetime, whatsapp calls, instagram calls or even snapchat calls, but it works fine on Sim calls. I have tried everything by rebooting, troubleshooting and also reinstalling the apps but still doesn't work. What could possibly be the issue. Very nervous about my phone having the issue or the software has it? And yes, i also tested mic's they all are recording correctly. Help needed. Thanks

[Re-Titled by Moderator]

Original Title: iphone not activating voice isolation