Random charge on my account

[LetYouDown]

Recently moved to Florida from NY. Liked my bank up north, don't even get me started on banks down here. Anyway, I've moved the vast majority of my recurring monthly accounts to my new debit card and that aspect is fine. My plan was to fizzle out my NY debit card until the account was virtually empty and then close it and get my check for $4.04 or whatever.

I was down to $78 left in the account when all of a sudden, this charge for $100 appears from "Systems Network" in Salinas, CA. Does ANYONE know what this could be? It's causing me to overdraw (which isn't cheap) and it's exactly $100. Haven't been to CA in 15 years, nor do I recall using my old card for anything that costs $100. I never had a recurring transaction of this amount. It strikes me as very strange. Currently it's pending against my account and my northern bank can't tell me anything about it until it clears (and I have to pay the overdraw fee).

Does anyone know what "Systems Network" in Salinas, CA is? It's such a ridiculous name that I can't even google it and find anything relevant.