Comment 4 for bug 1855415

You have one of the largest apt lists I have ever seen! You will notice that your attempt to update fails. There are a number of repos that return a 403 (forbidden) or 404 (missing).

When ubuntu-advantage-tools activates ESM, it attempts to do an apt update. If that fails, as it does in your case, the enable is reverted.

Therefore, if you clean up your various repos, and get apt update to exit cleanly, enabling ubuntu-advantage-tools should work.