diff --git a/Dockerfile b/Dockerfile
index b916f9c..7b3e4d6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -6,7 +6,7 @@ RUN npm install && \
 
 FROM python:3.10-slim-bullseye
 
-ENV VERSION_NUMBER 0.1.0-36-ge6b5804
+ENV VERSION_NUMBER 0.1.0-37-g76bf03b
 ENV PROD 1
 
 RUN useradd --create-home --uid 1000 timetracker
diff --git a/src/web/common/util/time.py b/src/web/common/util/time.py
index f707f86..5da1689 100644
--- a/src/web/common/util/time.py
+++ b/src/web/common/util/time.py
@@ -22,6 +22,8 @@ def format_duration(
     minute_seconds = 60
     hour_seconds = 60 * minute_seconds
     day_seconds = 24 * hour_seconds
+    if not isinstance(duration, timedelta):
+        duration = timedelta(seconds=duration)
     seconds_total = int(duration.total_seconds())
     # timestamps where end is before start
     if seconds_total < 0: