diff --git a/deploy/cttso-ica-to-pieriandx-cdk/Changelog.md b/deploy/cttso-ica-to-pieriandx-cdk/Changelog.md
index 2c925fb..be2bc18 100644
--- a/deploy/cttso-ica-to-pieriandx-cdk/Changelog.md
+++ b/deploy/cttso-ica-to-pieriandx-cdk/Changelog.md
@@ -10,9 +10,10 @@ are nested under deploy/cttso-ica-to-pieriandx-cdk.
 
 * Updated submission columns
 
-### Hot fix
+### Hot fixes
 
 * Updated submission column [#124](https://github.com/umccr/cttso-ica-to-pieriandx/pull/124) (fixes [#123](https://github.com/umccr/cttso-ica-to-pieriandx/issues/123))
+* Update is_validation logic [#127](https://github.com/umccr/cttso-ica-to-pieriandx/pull/127) (fixes [#126](https://github.com/umccr/cttso-ica-to-pieriandx/issues/126)) 
 
 ## 2023-08-09
 
diff --git a/deploy/cttso-ica-to-pieriandx-cdk/lambdas/launch_available_payloads_and_update_cttso_lims_sheet/lambda_code.py b/deploy/cttso-ica-to-pieriandx-cdk/lambdas/launch_available_payloads_and_update_cttso_lims_sheet/lambda_code.py
index 0767801..17afd73 100644
--- a/deploy/cttso-ica-to-pieriandx-cdk/lambdas/launch_available_payloads_and_update_cttso_lims_sheet/lambda_code.py
+++ b/deploy/cttso-ica-to-pieriandx-cdk/lambdas/launch_available_payloads_and_update_cttso_lims_sheet/lambda_code.py
@@ -243,10 +243,10 @@ def get_libraries_for_processing(merged_df) -> pd.DataFrame:
     to_process_df["is_validation_sample"] = to_process_df.apply(
         lambda x: True
         if x.glims_is_validation is True
-        and (
-               pd.isnull(x.redcap_is_complete) or
-               not x.redcap_is_complete.lower() == "complete"
-               or x.redcap_sample_type.lower() == "validation"
+        or (
+               not pd.isnull(x.redcap_is_complete)
+               and x.redcap_is_complete.lower() == "complete"
+               and x.redcap_sample_type.lower() == "validation"
            )
         else False,
         axis="columns"