The autoliquidation could lead to a much more than 10 % lose in one day.
Sorry for your loss.

On a separate note:
Buy SPY ETFs: No, too risky for retail clients.
Buy SPX Options: Yes, not considered as risky for retail clients.
There is a new KID requirement and some major US ETFs (SPY, Qs etc) do not have it filed. There is a conspiracy theory that it was done to appease the European ETF providers. The KID (key investor document) forces to specify expectation of performance under various scenarios, which obviously is contrary to the US regs of “no performance prediction”.Why would a EU based client not be able to trade US listed ETFs. I have client's in many countries trading them.
thxThere is a new KID requirement and some major US ETFs (SPY, Qs etc) do not have it filed. There is a conspiracy theory that it was done to appease the European ETF providers. The KID (key investor document) forces to specify expectation of performance under various scenarios, which obviously is contrary to the US regs of “no performance prediction”.
Here is a bit more color: https://ontheregs.com/tag/priips/