diff --git a/kowalski/tests/test_alert_broker_ztf.py b/kowalski/tests/test_alert_broker_ztf.py
index 58c39330..ff3ab65b 100644
--- a/kowalski/tests/test_alert_broker_ztf.py
+++ b/kowalski/tests/test_alert_broker_ztf.py
@@ -1,5 +1,6 @@
 import fastavro
 import pytest
+from copy import deepcopy
 from kowalski.alert_brokers.alert_broker_ztf import ZTFAlertWorker
 from kowalski.config import load_config
 from kowalski.log import log
@@ -54,8 +55,9 @@ def test_make_thumbnails(self):
 
     def test_alert_filter__ml(self):
         """Test executing ML models on the alert"""
-        alert, _ = self.worker.alert_mongify(self.alert)
-        scores = self.worker.alert_filter__ml(alert)
+        alert, prv_candidates = self.worker.alert_mongify(self.alert)
+        all_prv_candidates = deepcopy(prv_candidates) + [deepcopy(alert["candidate"])]
+        scores = self.worker.alert_filter__ml(alert, all_prv_candidates)
         assert len(scores) > 0
         log(scores)
 
diff --git a/kowalski/utils.py b/kowalski/utils.py
index 6a7d3329..7d13b0d4 100644
--- a/kowalski/utils.py
+++ b/kowalski/utils.py
@@ -1171,7 +1171,8 @@ def __init__(self, alert, alert_history, models, label=None, **kwargs):
                 self.alert["candidate"]["jdstarthist"],
                 min([a["jd"] for a in alert_history]),
             )
-        except Exception:
+        except Exception as e:
+            log(f"Failed to compute jd_first_alert: {e}")
             self.alert["candidate"]["jd_first_alert"] = self.alert["candidate"][
                 "jdstarthist"
             ]
@@ -1184,10 +1185,14 @@ def __init__(self, alert, alert_history, models, label=None, **kwargs):
         # we define days_to_peak as the time between the first alert and the alert with the lowest magpsf
         # and we define days_since_peak as the time between the alert with the lowest magpsf and the current alert
         # first we define jd_at_peak_mag as the jd of the alert with the lowest magpsf
-        jd_at_peak_mag = min(
-            [a for a in alert_history if a.get("magpsf", None) is not None],
-            key=lambda x: x["magpsf"],
-        )["jd"]
+        try:
+            jd_at_peak_mag = min(
+                [a for a in alert_history if a.get("magpsf", None) is not None],
+                key=lambda x: x["magpsf"],
+            )["jd"]
+        except Exception as e:
+            log(f"Failed to compute jd_at_peak_mag: {e}")
+            jd_at_peak_mag = self.alert["candidate"]["jd"]
 
         self.alert["candidate"]["days_to_peak"] = (
             jd_at_peak_mag - self.alert["candidate"]["jd_first_alert"]