diff --git a/src/Model/Study.py b/src/Model/Study.py
index eee599058ac91b48f3f095a45365f525ecbb56aa..aed5d68905f24147c8f77d6f74086a1c0b7a51fd 100644
--- a/src/Model/Study.py
+++ b/src/Model/Study.py
@@ -230,16 +230,16 @@ class Study(SQLModel):
         )
         self.execute(
             "INSERT INTO info VALUES ('date', " +
-            f"'{self._date.timestamp()}')"
+            f"'{timestamp(self._date)}')"
         )
 
         self.execute(
             "INSERT INTO info VALUES ('creation_date', " +
-            f"'{self.creation_date.timestamp()}')"
+            f"'{timestamp(self.creation_date)}')"
         )
         self.execute(
             "INSERT INTO info VALUES ('last_save_date', " +
-            f"'{self.last_save_date.timestamp()}')"
+            f"'{timestamp(self.last_save_date)}')"
         )
 
         self._create_submodel()
diff --git a/src/View/Tools/PamhyrDelegate.py b/src/View/Tools/PamhyrDelegate.py
index 00e09eedb180e825dff0a2d3b82676baff3cb94c..1a9d4cbfb4b230da043119a53dd953bd1046b1d1 100644
--- a/src/View/Tools/PamhyrDelegate.py
+++ b/src/View/Tools/PamhyrDelegate.py
@@ -18,6 +18,8 @@
 
 import logging
 
+from tools import timestamp
+
 from PyQt5.QtCore import (
     Qt, QRect, QTime, QDateTime, pyqtSlot,
 )
@@ -55,8 +57,8 @@ class PamhyrExTimeDelegate(QItemDelegate):
         if self._mode == "time":
             model.setData(index, int(time.total_seconds()))
         else:
-            logger.debug(str(time.timestamp()))
-            model.setData(index, int(time.timestamp()))
+            logger.debug(str(timestamp(time)))
+            model.setData(index, int(timestamp(time)))
         editor.close()
         editor.deleteLater()
 
diff --git a/src/tools.py b/src/tools.py
index 422fcdd6513d9412f9924e06f64c0ebc6b44ccc7..d7ba936d24f14f068a60295f516be52f084c80a5 100644
--- a/src/tools.py
+++ b/src/tools.py
@@ -237,7 +237,7 @@ def timestamp(dt: datetime):
 
 def date_iso_to_timestamp(date: str):
     if type(date) is str:
-        return datetime.fromisoformat(date).timestamp()
+        return timestamp(datetime.fromisoformat(date))
     else:
         return datetime.isoformat(date)