The product archive package's signature is invalid

The product archive package's signature is invalid. Ensure that it is signed with your "3rd Party Mac Developer Installer" certificate. (90237)

I'm receiving this error, despite the fact that I'm using this certificate when creating the pkg (with electron-forge)

My configuration is shown below - note the 3rd Party Mac Developer Installer identity when using new MakerPKG.

const config: ForgeConfig = {
  packagerConfig: {
    asar: true,
    name: 'Deep Focus',
    icon: 'resources/icon.icns',
    osxSign: {
      identity: 'Apple Distribution: Timeo Williams (3Y4F3KTSJA)',
      type: 'distribution',
      provisioningProfile: '/Users/timeo/Desktop/Deep Focus/deepWork/distribution.provisionprofile',
      preAutoEntitlements: false,
      // eslint-disable-next-line @typescript-eslint/explicit-function-return-type
      optionsForFile() {
        return {
          entitlements: 'build/entitlements.mas.plist'
        }
      }
    },
    extendInfo: 'build/info.plist',
    osxUniversal: {
      mergeASARs: true
    },
    appCategoryType: 'public.app-category.productivity',
    appBundleId: 'com.electron.deepfocus',
    extraResource: [
      'resources/.env',
      'resources/icon.icns',
    ]
  },
  rebuildConfig: {},
  makers: [
    new MakerSquirrel({}),
    new MakerZIP({}),
    new MakerRpm({}),
    new MakerDeb({}),
    new MakerDMG({
      appPath: './out/Deep Focus-darwin-arm64/Deep Focus.app',
      name: 'Deep Focus',
      icon: './resources/icon.icns',
      format: 'ULFO',
      overwrite: true,
      contents: (opts) => [
        { x: 130, y: 220, type: 'file', path: opts.appPath },
        { x: 410, y: 220, type: 'link', path: '/Applications' }
      ]
    }),
    new MakerPKG({
      name: 'Deep Focus',
      identity: '3rd Party Mac Developer Installer: Timeo Williams (3Y4F3KTSJA)'
    })
  ],
  plugins: [
    new VitePlugin({
      build: [
        {
          entry: 'src/main.ts',
          config: 'vite.main.config.ts',
          target: 'main'
        },
        {
          entry: 'src/preload.ts',
          config: 'vite.preload.config.ts',
          target: 'preload'
        }
      ],
      renderer: [
        {
          name: 'main_window',
          config: 'vite.renderer.config.mts' // Path to Vite config for renderer process
        }
      ]
    }),
    new FusesPlugin({
      version: FuseVersion.V1,
      [FuseV1Options.RunAsNode]: false,
      [FuseV1Options.EnableCookieEncryption]: true,
      [FuseV1Options.EnableNodeOptionsEnvironmentVariable]: false,
      [FuseV1Options.EnableNodeCliInspectArguments]: false,
      [FuseV1Options.EnableEmbeddedAsarIntegrityValidation]: true,
      [FuseV1Options.OnlyLoadAppFromAsar]: true
    })
  ]
}

Yet, I'm getting the error from Transporter that it's invalid?