diff --git a/app/brm/brn.py b/app/brm/brn.py
index 5e7b998..c30f39c 100644
--- a/app/brm/brn.py
+++ b/app/brm/brn.py
@@ -28,10 +28,10 @@ class BRN:
     def from_str(cls, s: str) -> BRN:
         parts = s.split(":")
         if len(parts) != 6 or parts[0].lower() != "brn" or not is_integer(parts[2]):
-            raise TypeError(f"Expected a valid BRN but got {repr(s)}.")
-        resource_parts = parts[4].split("/")
-        if len(resource_parts) != 5:
-            raise TypeError(f"Expected a valid BRN but got {repr(s)}.")
+            raise TypeError(f"Expected a valid BRN but got {repr(s)} (invalid parts).")
+        resource_parts = parts[5].split("/")
+        if len(resource_parts) != 2:
+            raise TypeError(f"Expected a valid BRN but got {repr(s)} (invalid resource parts).")
         return cls(
             global_namespace=parts[1],
             group_id=int(parts[2]),