Had the same problem, managed to install it after waiting abt a year after. The cause was apparently a bug in the installer. But recently that happens also every time when updating. Slim chance you will be able to update your instance of cloudpanel. I believe users need to be made aware of that before deciding to use cloudpanel. My final solution was moving away my sites one at a time to another popular, also open source, panel and my life has been a lot easier. Though I commend and recommend for its ease of use and power, cloudpanel need to work more on both its updater and installer. Will probably reuse it if fixed