TomSim on React "No Data Check" replacement doesn't work

I use React condition "No Data Check" to trigger action ThingHTTP with %%trigger%%  and %%channel_id%% in the action's body but the posted data doesn't expand the replacement key words (I just see the text %%trigger%% and %%channel_id%% in posted data).

The same replacements work fine with React numeric condition type.  What am I missing?

Thanks for any help.