diff --git a/src/main/scala/uncore/tilelink2/Fragmenter.scala b/src/main/scala/uncore/tilelink2/Fragmenter.scala
index 0325c20f..4fcef13e 100644
--- a/src/main/scala/uncore/tilelink2/Fragmenter.scala
+++ b/src/main/scala/uncore/tilelink2/Fragmenter.scala
@@ -174,7 +174,7 @@ class TLFragmenter(val minSize: Int, val maxSize: Int, val alwaysMin: Boolean =
       if (earlyAck) {
         // If you do early Ack, errors may not be dropped
         // ... which roughly means: Puts may not fail
-        assert (!out.d.bits.error || !drop)
+        assert (!out.d.valid || !out.d.bits.error || !drop)
         in.d.bits.error := out.d.bits.error
       } else {
         // Combine the error flag