diff --git a/asf_core_data/pipeline/mcs/process/process_historical_mcs_installers.py b/asf_core_data/pipeline/mcs/process/process_historical_mcs_installers.py
index 22b7dfb..7feea26 100644
--- a/asf_core_data/pipeline/mcs/process/process_historical_mcs_installers.py
+++ b/asf_core_data/pipeline/mcs/process/process_historical_mcs_installers.py
@@ -264,8 +264,7 @@ def get_missing_installers_info(
 
     # dropping unecessary variables
     missing_installers.drop(
-        columns=["date_of_creation"],
-        inplace=True,
+        columns=["date_of_creation"], inplace=True,
     )
 
     return missing_installers
@@ -609,6 +608,11 @@ def update_effective_to_date(
         right_on=installations_match_vars,
     )
 
+    installer_data["effective_to"] = pd.to_datetime(installer_data["effective_to"])
+    installer_data["commissioning_date"] = pd.to_datetime(
+        installer_data["commissioning_date"]
+    )
+
     installer_data["effective_to"] = installer_data.apply(
         lambda x: get_max_date(x["effective_to"], x["commissioning_date"]), axis=1
     )