Grandstream GXP2120 voicemail doesn't work

Hi I’m using FreePBX on fresh VPS instance.

I got the time condition / group and call flow to work which is one of our requirements and everything seems to be working fine. However one thing that doesn’t work is accessing voice mail using the hardware button.

We use Grandstream GXP2120 and the Envelope button when pressed doesn’t do anything. In phone settings I set it to *97.

When I dial *97 from the phone it does go to the inbox and prompts for password.

When i switch to another VOIP provider and register an extension VM button works (it’s accessed by dialing an extension or setting the extension # in the voicemail ID field in phone settings). Must be a different PBX software under the hood since VM is accessed by dialing extension.

So the button works, it just doesn’t like *97 which im trying to sent from my phone to VPS? How can i narrow down what is stopping it from sending *97 but it works with another provider ?

I tested two phones one with older firmware and another with the latest and both behave the same. Other hardware buttons (DND/ Call Transfer/ Hold) work as expected.

Any input is highly appreciated.