diff --git a/Dockerfile.alpine b/Dockerfile.alpine
index d2d7236..72fa8be 100644
--- a/Dockerfile.alpine
+++ b/Dockerfile.alpine
@@ -64,5 +64,44 @@ COPY . .
 RUN chmod +x *.sh && \
 	dos2unix *.sh
 
+# Set default values to prevent issues
+ENV DRYRUN="True"
+ENV DEBUG_LEVEL="INFO"
+ENV RUN_ONLY_ONCE="False"
+ENV SLEEP_DURATION=3600
+ENV LOG_FILE="log.log"
+ENV MARK_FILE="mark.log"
+ENV REQUEST_TIME=300
+ENV GENERATE_GUIDS="True"
+ENV GENERATE_LOCATIONS="True"
+ENV MAX_THREADS=1
+ENV USER_MAPPING=""
+ENV LIBRARY_MAPPING=""
+ENV BLACKLIST_LIBRARY=""
+ENV WHITELIST_LIBRARY=""
+ENV BLACKLIST_LIBRARY_TYPE=""
+ENV WHITELIST_LIBRARY_TYPE=""
+ENV BLACKLIST_USERS=""
+ENV WHITELIST_USERS=""
+ENV PLEX_BASEURL=""
+ENV PLEX_TOKEN=""
+ENV PLEX_USERNAME=""
+ENV PLEX_PASSWORD=""
+ENV PLEX_SERVERNAME=""
+ENV SSL_BYPASS="False"
+ENV JELLYFIN_BASEURL=""
+ENV JELLYFIN_TOKEN=""
+ENV EMBY_BASEURL=""
+ENV EMBY_TOKEN=""
+ENV SYNC_FROM_PLEX_TO_JELLYFIN="True"
+ENV SYNC_FROM_PLEX_TO_PLEX="True"
+ENV SYNC_FROM_PLEX_TO_EMBY="True"
+ENV SYNC_FROM_JELLYFIN_TO_PLEX="True"
+ENV SYNC_FROM_JELLYFIN_TO_JELLYFIN="True"
+ENV SYNC_FROM_JELLYFIN_TO_EMBY="True"
+ENV SYNC_FROM_EMBY_TO_PLEX="True"
+ENV SYNC_FROM_EMBY_TO_JELLYFIN="True"
+ENV SYNC_FROM_EMBY_TO_EMBY="True"
+
 ENTRYPOINT ["tini", "--", "/app/entrypoint.sh"]
 CMD ["python", "-u", "main.py"]
diff --git a/Dockerfile.slim b/Dockerfile.slim
index 7082901..114468b 100644
--- a/Dockerfile.slim
+++ b/Dockerfile.slim
@@ -38,5 +38,44 @@ ENV PATH="/app/.venv/bin:$PATH"
 RUN chmod +x *.sh && \
     dos2unix *.sh
 
+# Set default values to prevent issues
+ENV DRYRUN="True"
+ENV DEBUG_LEVEL="INFO"
+ENV RUN_ONLY_ONCE="False"
+ENV SLEEP_DURATION=3600
+ENV LOG_FILE="log.log"
+ENV MARK_FILE="mark.log"
+ENV REQUEST_TIME=300
+ENV GENERATE_GUIDS="True"
+ENV GENERATE_LOCATIONS="True"
+ENV MAX_THREADS=1
+ENV USER_MAPPING=""
+ENV LIBRARY_MAPPING=""
+ENV BLACKLIST_LIBRARY=""
+ENV WHITELIST_LIBRARY=""
+ENV BLACKLIST_LIBRARY_TYPE=""
+ENV WHITELIST_LIBRARY_TYPE=""
+ENV BLACKLIST_USERS=""
+ENV WHITELIST_USERS=""
+ENV PLEX_BASEURL=""
+ENV PLEX_TOKEN=""
+ENV PLEX_USERNAME=""
+ENV PLEX_PASSWORD=""
+ENV PLEX_SERVERNAME=""
+ENV SSL_BYPASS="False"
+ENV JELLYFIN_BASEURL=""
+ENV JELLYFIN_TOKEN=""
+ENV EMBY_BASEURL=""
+ENV EMBY_TOKEN=""
+ENV SYNC_FROM_PLEX_TO_JELLYFIN="True"
+ENV SYNC_FROM_PLEX_TO_PLEX="True"
+ENV SYNC_FROM_PLEX_TO_EMBY="True"
+ENV SYNC_FROM_JELLYFIN_TO_PLEX="True"
+ENV SYNC_FROM_JELLYFIN_TO_JELLYFIN="True"
+ENV SYNC_FROM_JELLYFIN_TO_EMBY="True"
+ENV SYNC_FROM_EMBY_TO_PLEX="True"
+ENV SYNC_FROM_EMBY_TO_JELLYFIN="True"
+ENV SYNC_FROM_EMBY_TO_EMBY="True"
+
 ENTRYPOINT ["/bin/tini", "--", "/app/entrypoint.sh"]
 CMD ["python", "-u", "main.py"]
diff --git a/src/main.py b/src/main.py
index 9dd0b5c..f3dfe66 100644
--- a/src/main.py
+++ b/src/main.py
@@ -96,12 +96,14 @@ def main_loop():
     dryrun = str_to_bool(os.getenv("DRYRUN", "False"))
     logger.info(f"Dryrun: {dryrun}")
 
-    user_mapping = os.getenv("USER_MAPPING", "")
-    user_mapping = json.loads(user_mapping.lower())
+    user_mapping = os.getenv("USER_MAPPING", None)
+    if user_mapping:
+        user_mapping = json.loads(user_mapping.lower())
     logger.info(f"User Mapping: {user_mapping}")
 
-    library_mapping = os.getenv("LIBRARY_MAPPING", "")
-    library_mapping = json.loads(library_mapping)
+    library_mapping = os.getenv("LIBRARY_MAPPING", None)
+    if library_mapping:
+        library_mapping = json.loads(library_mapping)
     logger.info(f"Library Mapping: {library_mapping}")
 
     # Create (black/white)lists