Update src/pages/messaging/agent-chat-api/v3.6/rtm-reference/index.mdx

Co-authored-by: Ola <[email protected]>

Author: lpmichalik

src/pages/messaging/agent-chat-api/v3.6/rtm-reference/index.mdx

@@ -2485,7 +2485,7 @@ If the number of tracked customers exceeds the limit, the `subscribed_customers_
 
 ### Unsubscribe Customers
 
-Removes a customers subscription.
+Removes a customer subscription.
 
 #### Specifics