This guide will tell you how to fix Downloading Necessary Game Data Not Working in Mortal Kombat Mobile.
The first thing you will need to do is open your play store app, search Mortal Kombat and uninstall this game. Once the uninstallation process finishes, you need to go to your device settings, scroll all the way down to Apps and tap on it.
Now you are in the apps section, you have to search for the Google play store app and tap on Storage and Cache. After that, click on Clear Cache and then click on the three dots in the right top corner of your screen. Then you need to click on Uninstall updates.
After that, again open the play store and search Mortal Kombat. Now you have to install the game back into your phone. It will fix your issue.