Schwab allowing concentrated trades then instantly remargining

I opened a position in ETHA and then added to the position which Schwab allowed. Then they instantly changed the margin on it to deeply negative.They let it sit out there for a few days and I think I only got one email about this. But, when I talked to customer service in the chat, they did not make any mention of any issue with my account when I was discussing ethereum in general.When I talked to customer service today they said that the reason it was closed out was because of concentrated risk and that they will allow me to open a trade like that and they can close it at their discretion. And they won't stop me from opening it. That's the part I have a problem with, if you're going to close it out then don't let me open it in the first place. via /r/u_SeaworthinessNo1414 https://ift.tt/Flf9MCi