When you perform a maintenance update, the update itself does not automatically update the extension versions that are used.
The reason for this is that user schemas and functions often rely on a specific version of an extension. Changing the underlying assumption behind that would break our customers' code.
Instead, you have to upgrade the extensions explicitly. This is common even if you run PostgreSQL on your own and just upgrade to a newer package version of an extension - that does not automatically update the extension in the databases either.
To update an extension, run the following command::
ALTER EXTENSION extensionname UPDATE;
extensionname to the latest available version.