Remote web trigger not working reliably

Check this thread for some tips -- unreliability is usually because your Mac can't maintain a "long poll" connection to the server.

One way round this problem is to use a cloud service and a "watched folder" trigger instead -- create a file in a "TriggerFolder" and have a single "watcher" macro that spots that new file, fires off the appropriate macro (based on file name or contents), then deletes the file.