Hi Kaotik!
There’s a few steps we can take to try and resolve that issue for you. 
Firstly, please fully close the Blizzard App, and any Blizzard games, and then uninstall the App as per this guide.
Next, please delete all the Blizzard App files, some of which may be left over after uninstallation, by following this guide.
Finally, please download and install the App again via this link.
Hopefully that will then resolve it for you!
Yours,
Arythwinn