Hi Ektratt,
welcome to the Apple (user-to-user) Community.
Re: AirPods 2 Pro hearing test not available on iPhone 11 Pro
Seems, although may countries have, not all authorities in the various countries have authorised its use.
See Apple support's list of the three new hearing features, fot the list of countries in which each is available.
AirPods Pro 2 - Hearing Health Feature Availability - Apple
Re: What is wrong?
If you find your country or region is listed:
"To take the Hearing Test, you need AirPods Pro 2 with the latest firmware
paired with an iPhone or iPad running iOS or iPadOS 18.1 or later.
Please see how to prepare for the test: Take a Hearing Test with AirPods Pro 2 - Apple Support
All the best :-)