diff --git a/src/libslic3r/Model.cpp b/src/libslic3r/Model.cpp
index b7623e27a..9fe12bb3b 100644
--- a/src/libslic3r/Model.cpp
+++ b/src/libslic3r/Model.cpp
@@ -3107,7 +3107,7 @@ void ModelVolume::update_extruder_count_when_delete_filament(size_t extruder_cou
     std::vector<int> used_extruders = get_extruders();
     for (int extruder_id : used_extruders) {
         if (extruder_id == filament_id) {
-            mmu_segmentation_facets.set_enforcer_block_type_limit(*this, (EnforcerBlockerType)(extruder_count + 1), (EnforcerBlockerType)(filament_id + 1), (EnforcerBlockerType)(replace_filament_id + 1));
+            mmu_segmentation_facets.set_enforcer_block_type_limit(*this, (EnforcerBlockerType)(extruder_count), (EnforcerBlockerType)(filament_id), (EnforcerBlockerType)(replace_filament_id));
             break;
         }
     }
diff --git a/src/libslic3r/TriangleSelector.cpp b/src/libslic3r/TriangleSelector.cpp
index 222c7e668..d9e8b8654 100644
--- a/src/libslic3r/TriangleSelector.cpp
+++ b/src/libslic3r/TriangleSelector.cpp
@@ -1768,13 +1768,17 @@ void TriangleSelector::deserialize(const std::pair<std::vector<std::pair<int, in
             }
 
             // BBS
-            if (state > max_ebt || state == to_delete_filament)
+            if (state == to_delete_filament)
                 state = replace_filament;
-
-            if (to_delete_filament != EnforcerBlockerType::NONE && state != EnforcerBlockerType::NONE) {
+            else if (to_delete_filament != EnforcerBlockerType::NONE && state != EnforcerBlockerType::NONE) {
                 state = state > to_delete_filament ? EnforcerBlockerType((int)state - 1) : state;
             }
 
+            if (state > max_ebt) {
+                assert(false);
+                state = EnforcerBlockerType::NONE;
+            }
+
             // Only valid if is_split.
             int special_side = code >> 2;
 
diff --git a/src/slic3r/GUI/Plater.cpp b/src/slic3r/GUI/Plater.cpp
index a49c6c6e4..0978afb57 100644
--- a/src/slic3r/GUI/Plater.cpp
+++ b/src/slic3r/GUI/Plater.cpp
@@ -1974,7 +1974,7 @@ void Sidebar::delete_filament(size_t filament_id, int replace_filament_id) {
 
     wxGetApp().preset_bundle->update_num_filaments(filament_id);
     wxGetApp().plater()->get_partplate_list().on_filament_deleted(filament_count, filament_id);
-    wxGetApp().plater()->on_filaments_delete(filament_count, filament_id, replace_filament_id > filament_id ? (replace_filament_id - 1) : replace_filament_id);
+    wxGetApp().plater()->on_filaments_delete(filament_count, filament_id, replace_filament_id > (int)filament_id ? (replace_filament_id - 1) : replace_filament_id);
     wxGetApp().get_tab(Preset::TYPE_PRINT)->update();
     wxGetApp().preset_bundle->export_selections(*wxGetApp().app_config);
 }
@@ -13422,7 +13422,7 @@ void Plater::on_filaments_delete(size_t num_filaments, size_t filament_id, int r
     // update mmu info
     for (ModelObject *mo : wxGetApp().model().objects) {
         for (ModelVolume *mv : mo->volumes) {
-            mv->update_extruder_count_when_delete_filament(num_filaments, filament_id, replace_filament_id);
+            mv->update_extruder_count_when_delete_filament(num_filaments, filament_id + 1, replace_filament_id + 1);  // this function is 1 base
         }
     }
 
diff --git a/src/slic3r/GUI/Plater.hpp b/src/slic3r/GUI/Plater.hpp
index 6f02def15..9906097e1 100644
--- a/src/slic3r/GUI/Plater.hpp
+++ b/src/slic3r/GUI/Plater.hpp
@@ -141,7 +141,7 @@ public:
     void on_filaments_delete(size_t filament_id);
 
     void add_filament();
-    void delete_filament(size_t filament_id = size_t(-1), int replace_filament_id = -1);  // 0 base
+    void delete_filament(size_t filament_id = size_t(-1), int replace_filament_id = -1);  // 0 base, -1 means default
     void change_filament(size_t from_id, size_t to_id);  // 0 base
     void edit_filament();
     void add_custom_filament(wxColour new_col);