@JoseCampos, I tried it myself and it worked for me. I wonder if you're using the bookmark token, not the one on the Instructions page? The bookmark token won't work.
Or, maybe you're using the voice field value for either the trigger or the computer? That won't work either.
My URL is: https://www.triggercmd.com/api/IFTTT?trigger=calculator&computer=ds
My method: POST
My content type: application/x-www-form-urlencoded
My body: token=eyJ.... (with no spaces)