I am an NRI customer. What happens if the scrip in which I have an SIP gets blocked due to RBI regulations?

If the SIP contains only those scrips which later have been blocked, then the entire SIP will get cancelled. However, if only some scrips in SIP are blocked then only that scrip will not be triggered, remaining SIP will be executed. Later if RBI restriction is removed, SIP won’t get re-activated for that scrip on its own. You will have to register for a new SIP.