You are not making trouble. You reported an issue (and you did some research
).
Sites do change and the plugins may need
adjustment from time to time.
If you have these kinds of troubles, be sure to update the associated plugin and Calibre.
If the update CAUSES the issue and a rollback to the previous version does not: Raise the flag by posting here (for plugins) and filing a bug report if it is the Base Calibre that seems to be the issue.
There are many-many pieces that must fit together perfectly for all to work