I'm so sorry about this, Miss Lea!

I ran the number and it appears to be VOIP, which means to figure out who it is is more complicated because it could be a Skype or Google number. I recommend that you go to both Skype/Microsoft and Google and send them screenshots of these texts.

If I may suggest that you, or anyone else, receives these kind of threatening texts or emails in the future, do not engage with the person. Just report and block. These types of people get off on your attention and fear. If they don't get it they will move on.