Comment # 21 on bug 1214135 from Ladislav Slezák

Changing the URL is a bit tricky, in that case YaST actually deletes the old
repository (to force removing all cached files) and creates a new repository
with the new URL. Then YaST copies all attributes (enabled/disabled,
priority,...) from the old repository to the new one.

And here was the bug, YaST did not copy the "service" attribute so the new
repository had the same name as the old one, but was not bound to the original
service. For libzypp it looks like a standalone repository and when libzypp
refreshed the service it found out that a conflicting repository already
exists.

Additionally a warning that the repository is managed by a service is now
displayed when changing the repository URL. The same warning is already
displayed when changing other repository attributes (enabled/disabled,
priority,...), it was missing when changing the URL.

(More details in https://github.com/yast/yast-packager/pull/642)

Fixed in yast2-packager-5.0.1 (Tumbleweed) and yast2-packager-4.6.4
(SLE15-SP6/Leap15.6).