I totally get what you're going through with the proximity sensor and screen light issue while listening to WhatsApp voice messages on your iPhone 14 Pro Max. I actually faced the same problem, but guess what? I managed to fix it! Here's what worked for me:
First, I gave my iPhone a good old restart. It's surprising how often that simple trick does the trick!
Next, I made sure to update WhatsApp to the latest version. Those updates often come with bug fixes and improvements that can solve pesky issues like this one.
If the problem still persisted, I went ahead and reset my iPhone's settings. It didn't erase any of my data, but it did reset my preferences and settings back to their default values.
As a last resort, I uninstalled WhatsApp and then reinstalled it from the App Store. Sometimes starting fresh can make all the difference.
After going through these steps, I'm happy to report that everything is working smoothly now! But if you're still stuck, I'd recommend getting in touch with Apple Support or visiting an Apple Store. They're the experts and can offer more specific help.
Oh, and don't forget to back up your important stuff regularly, just to be safe. Hope these tips do the trick for you too! Good luck, and let me know if you have any more questions!.