Cocoapods cache not working properly

Hi. My repo has the following directory structure:

tree -L 1 .     
├── MyApplication
├── Data
├── Domain
└── scripts

The problem is that using the following steps, Cocoapods dependencies gets not cached properly:

      - uses: actions/checkout@v2
      - name: Rehydrate Cocoapods cache
        uses: actions/cache@v2
          path: 'MyApplication/Pods'
          key: ${{ runner.os }}-pods-${{ hashFiles('**/Podfile.lock') }}
          restore-keys: |
            ${{ runner.os }}-pods-

Post [...] Output

Cache Size: ~0 MB (22 B)
Cache saved successfully
Cache saved with key: macOS-pods-7c10eb67104e94a5a8bd0cab9901c33963d6453d47e2bb1e0281130b3482293b

Of course, we have a pod install step after the cache rehydration, and it completes successfully. What are we doing wrong?