First of all, the first question: if the available funds are negative, there is a certain risk of forced liquidation at this time, and there will be no forced liquidation above this risk. This is different for every securities company with an account. Of course, it is better to have a new transfer of funds.

Secondly, the second question: if it goes up, the available funds will definitely go up.

Finally, the third question, if there is profit, you can use floating funds to open a new contract.

In fact, generally speaking, individuals are not recommended to do stock index futures. First, the handling fee is high, and second, the trading is not very active. If you want to do margin trading, I suggest you do domestic commodity futures, with low leverage, large fluctuations and active trading!

Handmade, hope to adopt, thank you!