You might have missed here is adding "App attest" capability to your build targets in XCode as per docs here: https://firebase.google.com/docs/app-check/ios/app-attest-provider?hl=en&authuser=0&\_gl=1\*pye4gi\*\_ga\*MjQ1OTY5MjU0LjE3MjM0NTEzMTM.\*\_ga_CW55HF8NVT\*MTc0NTU1ODYxNi4zOS4xLjE3NDU1NjAwNjIuNTkuMC4w#install-sdk

Make sure the environment is also correct as attestation with debug token will not work if environment is set to `production` & production mode attestation will not work if environment is `development`.