diff --git a/umap/plot.py b/umap/plot.py
index 1d54d322..db19ac64 100644
--- a/umap/plot.py
+++ b/umap/plot.py
@@ -1589,5 +1589,4 @@ def nearest_neighbour_distribution(umap_object, bins=25, ax=None):
 
     ax.hist(nn_distances, bins=bins)
 
-    return ax
-
+    return ax
\ No newline at end of file
diff --git a/umap/utils.py b/umap/utils.py
index 3e2bb28a..0f3c9dc6 100644
--- a/umap/utils.py
+++ b/umap/utils.py
@@ -212,6 +212,9 @@ def average_nn_distance(dist_matrix):
     averages = sum_non_zero_elems/count_non_zero_elems
 
     if any(np.isnan(averages)):
-        warn("Embedding contains disconnected vertices which will be ignored. Use umap.utils.disconnected_vertices() to identify them.")
-    
-    return averages
+        warn(
+            "Embedding contains disconnected vertices which will be ignored." 
+            "Use umap.utils.disconnected_vertices() to identify them."
+        )
+
+    return averages
\ No newline at end of file