HELP! Battle.net refuses to update or install COD MW

It started when I tried to update COD Warzone, and it just wouldn’t start, switched from 0Bytes to “waiting for another installation”. restarted the computer, checked for viruses, uninstall and then reinstall battle.net, delete its cache, uninstall the game, and restart the modem. all of these didn’t work, and now I not only have to update the game but to download it completely, and it still is stuck on 0Bytes.