The targetSdkVersion must be configured in the expo-build-properties plugin, NOT directly in the android block of your app config like this:

  {
    "expo": {
      "plugins": [
        [
          "expo-build-properties",
          {
            "android": {
              "compileSdkVersion": 35,
              "targetSdkVersion": 35,
              "buildToolsVersion": "35.0.0"
            }
          }
        ]
      ]
    }
  }

Reference: https://docs.expo.dev/versions/latest/sdk/build-properties/#example-appjson-with-config-plugin