diff --git a/flepimop/gempyor_pkg/src/gempyor/compartments.py b/flepimop/gempyor_pkg/src/gempyor/compartments.py
index 25ec19406..51ce16993 100644
--- a/flepimop/gempyor_pkg/src/gempyor/compartments.py
+++ b/flepimop/gempyor_pkg/src/gempyor/compartments.py
@@ -283,7 +283,7 @@ def fromFile(self, compartments_file, transitions_file):
 
         return
 
-    def get_comp_idx(self, comp_dict: dict) -> int:
+    def get_comp_idx(self, comp_dict: dict, error_info: str = "no information") -> int:
         """
         return the index of a compartiment given a filter. The filter has to isolate a compartiment,
         but it ignore columns that don't exist:
@@ -294,7 +294,7 @@ def get_comp_idx(self, comp_dict: dict) -> int:
         comp_idx = self.compartments[mask].index.values
         if len(comp_idx) != 1:
             raise ValueError(
-                f"The provided dictionary does not allow to isolate a compartment: {comp_dict} isolate {self.compartments[mask]} from options {self.compartments}"
+                f"The provided dictionary does not allow to isolate a compartment: {comp_dict} isolate {self.compartments[mask]} from options {self.compartments}. The get_comp_idx function was called by'{error_info}'." 
             )
         return comp_idx[0]
 
diff --git a/flepimop/gempyor_pkg/src/gempyor/seeding_ic.py b/flepimop/gempyor_pkg/src/gempyor/seeding_ic.py
index 8da628cb8..7dcdacee3 100644
--- a/flepimop/gempyor_pkg/src/gempyor/seeding_ic.py
+++ b/flepimop/gempyor_pkg/src/gempyor/seeding_ic.py
@@ -50,8 +50,8 @@ def _DataFrame2NumbaDict(df, amounts, setup) -> nb.typed.Dict:
                 )
                 source_dict = {grp_name: row[f"source_{grp_name}"] for grp_name in cmp_grp_names}
                 destination_dict = {grp_name: row[f"destination_{grp_name}"] for grp_name in cmp_grp_names}
-                seeding_dict["seeding_sources"][idx] = setup.compartments.get_comp_idx(source_dict)
-                seeding_dict["seeding_destinations"][idx] = setup.compartments.get_comp_idx(destination_dict)
+                seeding_dict["seeding_sources"][idx] = setup.compartments.get_comp_idx(source_dict, error_info = f"(seeding source at idx={idx}, row_index={row_index}, row=>>{row}<<)")
+                seeding_dict["seeding_destinations"][idx] = setup.compartments.get_comp_idx(destination_dict, error_info = f"(seeding destination at idx={idx}, row_index={row_index}, row=>>{row}<<)")
                 seeding_dict["seeding_subpops"][idx] = setup.subpop_struct.subpop_names.index(row["subpop"])
                 seeding_amounts[idx] = amounts[idx]
                 #id_seed+=1