InMobi SDK 7 Android | InMobi needs to be initialized before calling Interstitial Request

Question

I have integrated InMobi 7.2.9 in my App and initialize it like this:

  JSONObject consent = new JSONObject();
  try {
      consent.put(InMobiSdk.IM_GDPR_CONSENT_AVAILABLE, true);
  } catch (JSONException e) {
      Log.d(TAG, "Init InMobiSDK failed");
      e.printStackTrace();
  }
  InMobiSdk.init(cordova.getActivity(), accountID, consent);
  InMobiSdk.setLogLevel(InMobiSdk.LogLevel.DEBUG);

After that I initialize my Interstitial like this:

mInterstitialAd = new InMobiInterstitial(cordova.getActivity(), placementId,
   new InterstitialAdEventListener() {
       @Override
       public void onAdLoadSucceeded(InMobiInterstitial inMobiInterstitial) {
            super.onAdLoadSucceeded(inMobiInterstitial);
            Log.d(TAG, "onAdLoadSuccessful");
            if (!inMobiInterstitial.isReady()) {
              Log.d(TAG, "onAdLoadSuccessful inMobiInterstitial not ready");
            }
       }

       @Override
       public void onAdLoadFailed(InMobiInterstitial inMobiInterstitial, InMobiAdRequestStatus inMobiAdRequestStatus) {
           super.onAdLoadFailed(inMobiInterstitial, inMobiAdRequestStatus);
           Log.d(TAG, "Unable to load interstitial ad (error message: " + inMobiAdRequestStatus.getMessage());
       }

       @Override
       public void onAdReceived(InMobiInterstitial inMobiInterstitial) {
           super.onAdReceived(inMobiInterstitial);
           Log.d(TAG, "onAdReceived");
       }

       @Override
       public void onAdClicked(InMobiInterstitial inMobiInterstitial, Map<Object, Object> map) {
           super.onAdClicked(inMobiInterstitial, map);
           Log.d(TAG, "onAdClicked " + map.size());
       }

       @Override
       public void onAdWillDisplay(InMobiInterstitial inMobiInterstitial) {
           super.onAdWillDisplay(inMobiInterstitial);
           Log.d(TAG, "onAdWillDisplay " + inMobiInterstitial);
       }

       @Override
       public void onAdDisplayed(InMobiInterstitial inMobiInterstitial) {
           super.onAdDisplayed(inMobiInterstitial);
           Log.d(TAG, "onAdDisplayed " + inMobiInterstitial);
       }

       @Override
       public void onAdDisplayFailed(InMobiInterstitial inMobiInterstitial) {
           super.onAdDisplayFailed(inMobiInterstitial);
           Log.d(TAG, "onAdDisplayFailed " + "FAILED");
       }

       @Override
       public void onAdDismissed(InMobiInterstitial inMobiInterstitial) {
           super.onAdDismissed(inMobiInterstitial);
           Log.d(TAG, "onAdDismissed " + inMobiInterstitial);
       }

       @Override
       public void onUserLeftApplication(InMobiInterstitial inMobiInterstitial) {
           super.onUserLeftApplication(inMobiInterstitial);
           Log.d(TAG, "onUserWillLeaveApplication " + inMobiInterstitial);
       }

       @Override
       public void onRewardsUnlocked(InMobiInterstitial inMobiInterstitial, Map<Object, Object> map) {
           super.onRewardsUnlocked(inMobiInterstitial, map);
           Log.d(TAG, "onRewardsUnlocked " + map.size());
       }
   });

   Log.d(TAG, "Start to load Interstitial");
   mInterstitialAd.load();

To init the InMobi SDK I use the accountID from my InMobi Account and placementID for my Interstitial Ad.First I init my InMobi and after that I load the Interstitial. But somehow Im always getting the Erro:

You need to initialize InMobi first before calling Interstitial Ads. Call ignored.

I used this sample code from inmobi but somehow InmobiSdk.init doesnt work.