WP 3 Upgrade Disabled RSS Aggregator Plugin Edits

Our recent automatic Web 3.0 upgrade appears to have disabled the Administrator’s ability to edit the 2 RSS Aggregator plugins installed at https://www.ontariosoccer.ca/OSABlog .

The pre-upgrade installed feeds are still working on the site, but although feeds can be added (Step 1.), neither the original BDP-RSS Aggregator or the more recent Parteibuch Aggregator currently allow feed Edit, Delete, Create new output format, etc.

The page simply returns to Step 1. each time one of these functions is attempted.

These plugins have been alternately activated and de-activated without success. (They do not function simultaneously.)

Any advice would be appreciated.