diff --git a/circuitpython/code/main.py b/circuitpython/code/main.py
index 71181b7..6a3932f 100644
--- a/circuitpython/code/main.py
+++ b/circuitpython/code/main.py
@@ -256,17 +256,17 @@ def rotate_files():
     #If the hour changed : copy current data.csv to hourly directory
     if current_time[3] != last_time[3] and backup_data:
         print("Time to move hourly data !")
-        os.rename("data/data.csv", "data/hourly/{}.csv".format(last_time[3]))
+        os.rename("data/data.csv", "data/hourly/{:02}.csv".format(last_time[3]))
 
     #If the day changed : copy content of hourly to daily directories
     if current_time[2] != last_time[2] and backup_data:
         print("Time to move daily data !")
         #Create new dir for the date of yesterday
-        newdir = "data/daily/{}{}{}.csv".format(last_time[0:2])
+        newdir = "data/daily/{}{:02}{:02}".format(*last_time[0:3])
         os.mkdir(newdir)
         #Move each "hourly file" to the new directory
         for file in os.listdir('data/hourly'):
-            print("Move {} to {}".format(newdir, file))
+            print("Move {} to {}".format(file, newdir))
             os.rename("data/hourly/{}".format(file), "{}/{}".format(newdir, file))
 
     #Finally update last_time, each time