Signature verification failed in Expansion Files & In-App Purchase

Question

I have implemented expansion files and In-App Purchase in my app. And app published on beta channel.

While testing when i am downloading expansion files manually for testing below code giving me the error.

E/LicenseValidator: Signature verification failed.

String userId = null;
    // Skip signature check for unsuccessful requests
    ResponseData data = null;
    Log.i(TAG, "verify responseCode : " + responseCode);
    if (responseCode == LICENSED || responseCode == NOT_LICENSED ||
        responseCode == LICENSED_OLD_KEY) {
      // Verify signature.
      Log.i(TAG, "verify  signature : " + signature);
      try {
        Signature sig = Signature.getInstance(SIGNATURE_ALGORITHM);
        sig.initVerify(publicKey);
        sig.update(signedData.getBytes());

        if (!sig.verify(Base64.decode(signature))) {
          Log.e(TAG, "Signature verification failed.");
          handleInvalidResponse();
          return;
        }
      } catch (NoSuchAlgorithmException e) {

        throw new RuntimeException(e);
      } catch (InvalidKeyException e) {
        handleApplicationError(LicenseCheckerCallback.ERROR_INVALID_PUBLIC_KEY);
        return;
      } catch (SignatureException e) {
        throw new RuntimeException(e);
      } catch (Base64DecoderException e) {
        Log.e(TAG, "Could not Base64-decode signature.");
        handleInvalidResponse();
        return;
      } 

signature and signedData are not null or empty in response. And receiving responseCode equal to LICENSED

I have checked Base64 encoded public RSA key with Google play console key it is same. Code sig.verify(signatureBytes) always returning false.

Signature verification is also not working in In-App purchase with same app.