diff --git a/src/rntuple.cpp b/src/rntuple.cpp
index 8f2e551..7ab8053 100644
--- a/src/rntuple.cpp
+++ b/src/rntuple.cpp
@@ -353,7 +353,11 @@ RNTuple_Data get_rntuple_data(Arena *arena, const Inspected_File &file, const TF
               }
             }
 
-            assert(inserted != duplicate);
+            if (inserted == duplicate) {
+              fprintf(stderr, "WARNING: we were supposed to either add a page or recognize it as a duplicate, but %s "
+                              "true for page 0x%" PRIX64 " - 0x%" PRIX64 "!?\n",
+                              inserted ? "both things are" : "neither thing is", pinfo->range.start, pinfo->range.end());
+            }
           }
 
           if (duplicate) {
@@ -446,7 +450,10 @@ RNTuple_Data get_rntuple_data(Arena *arena, const Inspected_File &file, const TF
   }
 
   // verify that we added all pages to chunks
-  assert(idx == n_pages);
+  if (idx != n_pages) {
+    fprintf(stderr, "WARNING: we were supposed to add %" PRIu64 " pages but we added %" PRIu64 ": something very wrong"
+                    " is going on with this file!\n", n_pages, idx);
+  }
 
   if (n_groups) {
     Page_Info_Group &last_group = groups[n_groups - 1];