diff --git a/src/graphnet/data/dataconverter.py b/src/graphnet/data/dataconverter.py
index 94f14d31b..33e598867 100644
--- a/src/graphnet/data/dataconverter.py
+++ b/src/graphnet/data/dataconverter.py
@@ -336,8 +336,7 @@ def merge_files(
             # Proceed to merge specified by user.
             if isinstance(files, str):
                 # We shouldn't merge a single file?
-                self.info(f"Got just a single file {files}."
-                           "Merging skipped.")
+                self.info(f"Got just a single file {files}. Merging skipped.")
                 return
             files_to_merge = files
         else: