diff --git a/server_test.go b/server_test.go
index 0833cae2..8865e669 100644
--- a/server_test.go
+++ b/server_test.go
@@ -633,6 +633,8 @@ func TestSTUNOnly(t *testing.T) {
 
 	_, err = client.Allocate()
 	assert.Equal(t, err.Error(), "Allocate error response (error 400: )")
+
+	assert.NoError(t, conn.Close())
 }
 
 func RunBenchmarkServer(b *testing.B, clientNum int) { //nolint:cyclop