diff --git a/.changeset/strong-buttons-wink.md b/.changeset/strong-buttons-wink.md
new file mode 100644
index 000000000..c01fb390a
--- /dev/null
+++ b/.changeset/strong-buttons-wink.md
@@ -0,0 +1,5 @@
+---
+"@vue-flow/core": patch
+---
+
+Correct connection keys.
diff --git a/packages/core/src/utils/store.ts b/packages/core/src/utils/store.ts
index f6e86e317..eb8f28312 100644
--- a/packages/core/src/utils/store.ts
+++ b/packages/core/src/utils/store.ts
@@ -171,8 +171,8 @@ export function updateConnectionLookup(connectionLookup: ConnectionLookup, edgeL
     const { source: sourceNode, target: targetNode, sourceHandle = null, targetHandle = null } = edge
 
     const connection = { edgeId: edge.id, source: sourceNode, target: targetNode, sourceHandle, targetHandle }
-    const sourceKey = `${sourceNode}-${sourceHandle}`
-    const targetKey = `${targetNode}-${targetHandle}`
+    const sourceKey = `${sourceNode}-${sourceHandle}--${targetNode}-${targetHandle}`
+    const targetKey = `${targetNode}-${targetHandle}--${sourceNode}-${sourceHandle}`
 
     addConnectionToLookup('source', connection, targetKey, connectionLookup, sourceNode, sourceHandle)
     addConnectionToLookup('target', connection, sourceKey, connectionLookup, targetNode, targetHandle)