Hi there, I’m not sure what is causing this issue, but I would try exiting the launcher and reloading, then go to the library and try to remove the engine slots by clicking the ‘X’ in the top right corner of each slot. You will probably need to cancel all 3 downloads, exit the launcher and restart, then choose one version to install and press the download button. But make sure you are only downloading one at a time to avoid any issues.
An alternate way to cancel is to click the small ‘X’ beside the pause button on the Library tab.
If that doesn’t help, please go through this troubleshooting guide to get it back up and running:
Thanks!