@El-Kortungas, what does it show in your Runs list for the command? I just ran Calculator using the TRIGGERcmd Smart Home skill and it ran only once as you can see here:
63868947-3086-4a59-a7fc-5087967a20a4-image.png
Also, which Alexa skill are you using? The runs list will show that too. I recommend the TRIGGERcmd Smart Home skill.
You could try unlinking and re-linking the skill.