diff --git a/src/core/coap/coap.cpp b/src/core/coap/coap.cpp
index 8730c8e5a..a64d18d57 100644
--- a/src/core/coap/coap.cpp
+++ b/src/core/coap/coap.cpp
@@ -1302,7 +1302,7 @@ void CoapBase::ProcessReceivedRequest(Message &aMessage, const Ip6::MessageInfo
 {
     char     uriPath[Message::kMaxReceivedUriPath + 1];
     Message *cachedResponse = nullptr;
-    Error    error          = kErrorNotFound;
+    Error    error          = kErrorNone;
 #if OPENTHREAD_CONFIG_COAP_BLOCKWISE_TRANSFER_ENABLE
     Option::Iterator iterator;
     char *           curUriPath         = uriPath;
@@ -1320,10 +1320,10 @@ void CoapBase::ProcessReceivedRequest(Message &aMessage, const Ip6::MessageInfo
     case kErrorNone:
         cachedResponse->Finish();
         error = Send(*cachedResponse, aMessageInfo);
-
-        OT_FALL_THROUGH;
+        ExitNow();
 
     case kErrorNoBufs:
+        error = kErrorNoBufs;
         ExitNow();
 
     case kErrorNotFound:
@@ -1453,8 +1453,11 @@ void CoapBase::ProcessReceivedRequest(Message &aMessage, const Ip6::MessageInfo
     {
         mDefaultHandler(mDefaultHandlerContext, &aMessage, &aMessageInfo);
         error = kErrorNone;
+        ExitNow();
     }
 
+    error = kErrorNotFound;
+
 exit:
 
     if (error != kErrorNone)