diff --git a/src/geometry/broad_phase_multi_sap/sap_proxy.rs b/src/geometry/broad_phase_multi_sap/sap_proxy.rs
index 9ddd8b9..b1a1996 100644
--- a/src/geometry/broad_phase_multi_sap/sap_proxy.rs
+++ b/src/geometry/broad_phase_multi_sap/sap_proxy.rs
@@ -7,7 +7,7 @@ use std::ops::{Index, IndexMut};
 pub type SAPProxyIndex = u32;
 
 #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub enum SAPProxyData {
     Collider(ColliderHandle),
     Region(Option<Box<SAPRegion>>),
@@ -48,7 +48,7 @@ impl SAPProxyData {
 }
 
 #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct SAPProxy {
     pub data: SAPProxyData,
     pub aabb: Aabb,
diff --git a/src/geometry/broad_phase_multi_sap/sap_region.rs b/src/geometry/broad_phase_multi_sap/sap_region.rs
index 1a3903b..946f036 100644
--- a/src/geometry/broad_phase_multi_sap/sap_region.rs
+++ b/src/geometry/broad_phase_multi_sap/sap_region.rs
@@ -1,4 +1,5 @@
 use super::{SAPAxis, SAPProxies};
+use crate::geometry::broad_phase_multi_sap::DELETED_AABB_VALUE;
 use crate::geometry::SAPProxyIndex;
 use crate::math::DIM;
 use bit_vec::BitVec;
@@ -8,7 +9,7 @@ use parry::utils::hashmap::HashMap;
 pub type SAPRegionPool = Vec<Box<SAPRegion>>;
 
 #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct SAPRegion {
     pub axes: [SAPAxis; DIM],
     pub existing_proxies: BitVec,
@@ -187,12 +188,25 @@ impl SAPRegion {
     pub fn update_after_subregion_removal(&mut self, proxies: &SAPProxies, layer_depth: i8) {
         if self.needs_update_after_subregion_removal {
             for axis in &mut self.axes {
-                self.subproper_proxy_count -= axis
-                    .delete_deleted_proxies_and_endpoints_after_subregion_removal(
-                        proxies,
-                        &mut self.existing_proxies,
-                        layer_depth,
+                let num_deleted_proxies = axis.delete_deleted_proxies_and_endpoints_after_subregion_removal(
+                    proxies,
+                    &mut self.existing_proxies,
+                    layer_depth,
+                );
+                if num_deleted_proxies > self.subproper_proxy_count {
+                    let marked_as_deleted_count = proxies.elements.clone()
+                        .into_iter()
+                        .filter(|p| p.aabb.mins.x == DELETED_AABB_VALUE)
+                        .count();
+                    dbg!(marked_as_deleted_count);
+                    dbg!(num_deleted_proxies, self.subproper_proxy_count);
+                    dbg!(proxies.elements.clone());
+                    dbg!(
+                        self.needs_update_after_subregion_removal, self.update_count,
+                        self.subregions.clone(), self.to_insert.clone()
                     );
+                }
+                self.subproper_proxy_count -= num_deleted_proxies;
             }
             self.needs_update_after_subregion_removal = false;
         }