Configuration.set doesn't set value

Assuming the set actually set as the user doing the set call is the broadcaster (or better)

Then this woukd suggest the configuration service is not enabled

You can also use the API to cross check whats enabled

Or a tool, like my Extension Developer Tools will check whats enabled and enable relevant functions

So here for example it checked whats enabled (via Get Extensions) and saw the Config service is but Send Chat isn’t (for example)