Update src/protocols/faq.md

Author: forstisabella

src/protocols/faq.md

@@ -85,7 +85,7 @@ Segment's code uses built-in logic to verify if an event exists in the Tracking
 
 Unplanned property omission is only supported for cloud-mode destinations. Unplanned properties will not be omitted when they're sent to device-mode destinations.
 
-### Why do I have to different Tracking Plan IDs?
+### Why do I have two different Tracking Plan IDs?
 
 When you access a Tracking Plan, you'll come across two IDs: `tp_` and `rs_`.