Any issue with this third party plugin must be asked to the developer of the plugin.
It's known to cause multiple issues with latest versions of OBS. Their alert service is also plagued with errors that you can see in the log file. This errors are shown so the devs can see what's going on and fix it, but as you may notice this was never fixed.
If you only stream to Twitch it's better if you use their alerts as this ones rarely gives an error message.