Help understanding stop loss and why it is not executing

Hi. I have recently started a Zerodha account in February and I’m having trouble understanding options and M2M. As I understand call and put options have a set loss which is the price being paid. Basically the price paid for the call/put options is what can be the max loss in case the market does not move in favor of the call/put option buyer but I see that under MTM the market basically can wipe a person out. Please someone explain to me what is happening. 1. I purchased NiftyMay 7700 CE at RS 176 setting SL-M at 150. So according to the call option pricing RS 176 x 75 = RS 13,200 should be my max loss As the market started sliding below my SL-M of RS 150 Pi does not trigger. (Will detail later) As the price of the 7700 call falls to RS 137.40 I see my MTM has reached -3903 and I panic and exit. Also I set trigger price at RS 150 which did not execute. Basically there are 2 things happening. 1. Maybe I don’t get SL-M. I have opened 2 tickets with Zerodha regarding this before as well. I always place SL-M orders meaning the moment price hits trigger price a sell order will be sent to the exchange and I will get out of my position and minimize my loss. However every time the price goes below the trigger set by me and I have to MANUALLY exit the position. On the last ticket opened with Zerodha I got this reply. &quote “Your SL-M order has been rejected. The snapshot you have sent clearly shows that SL-M order is rejected due to margin shortfall. You have only placed a limit order. When you place a limit order, a separate exit order and stop loss orders have to be placed.” 2. If my max loss by purchasing a call option of NiftyMay7700 is RS. 13,200 what would happen if it reaches the this amount? I always panic and exit. This is seriously hindering my trading experience. It seems I am placing limit orders? So does that mean I cannot set automatic stop loss and MANUALLY exit the positions created? I basically want that when I place an order with SL-M and set trigger price then as soon as that trigger price is hit I can get out of the position and cover my losses. Thanking you all. Please run me through since there is a lot of confusion on stop loss not executing.