diff --git a/RecoLocalTracker/SiPixelClusterizer/plugins/gpuClusterChargeCut.h b/RecoLocalTracker/SiPixelClusterizer/plugins/gpuClusterChargeCut.h
index 093ef05717a0a..bac8a7bc53c7e 100644
--- a/RecoLocalTracker/SiPixelClusterizer/plugins/gpuClusterChargeCut.h
+++ b/RecoLocalTracker/SiPixelClusterizer/plugins/gpuClusterChargeCut.h
@@ -39,11 +39,16 @@ namespace gpuClustering {
     auto endModule = moduleStart[0];
     for (auto module = firstModule; module < endModule; module += gridDim.x) {
       auto firstPixel = moduleStart[1 + module];
-      while (id[firstPixel] == invalidModuleId)
-        ++firstPixel;  // could be duplicates!
+      while (id[firstPixel] == invalidModuleId) {
+        // could be duplicates!
+        ++firstPixel;
+      }
       auto thisModuleId = id[firstPixel];
+      if (thisModuleId != moduleId[module]) {
+        // all pixels are either invalid or duplicates, skip this module
+        continue;
+      }
       assert(thisModuleId < nMaxModules);
-      assert(thisModuleId == moduleId[module]);
 
       auto nclus = nClustersInModule[thisModuleId];
       if (nclus == 0)