The reward command is bugged on Aradune. Neither the EQ button or the /reward command will open the reward window.
Doesn't open if you have no pending rewards. Other than that, if you have a broken custom UI or broken UI_char_server.ini file.
This seems like a good QoL update. If, after using /reward, the window pops open and closes itself (which indicates there are no pending rewards, it should probably echo something to the chat window to indicate there are no pending rewards to be claimed on the character.