Our app Icon is displaying a black background and distorted in apple store

We have originally uploaded our app in the app store and it displayed our companies logo with a white background. However, we made some updates to the app and when it was put through the test build, the app icon went black and distorted. We do not have a transparent background and I have changed the background several times just to be sure and it is still displaying a black background. In fact we have downloaded over eight test builds displaying the same information. When I consulted with an apple engineer and what platform we were using to develop the app, we were told initially that it was an “Adalo” issue. We also utilized other third party platforms to upload apps in the past and have never faced this issue. Please help as it has been three weeks to no resolve and we are nonprofit helping the homeless where individuals cannot download the app correctly because it is distorted in the app store.

Is there anyone available?