Add expose to see if that fixes issue.

Dockerfile

@@ -20,4 +20,7 @@ COPY database_setup database_setup/
 
 RUN pip install -r requirements.txt
 
+# Expose to outside of container
+EXPOSE 5000
+
 CMD ["python3", "-u", "./main.py"]

cogs/commands/refresh.py

@@ -29,7 +29,6 @@ class RefreshCog(commands.Cog, name="Refresh Commands"):
         Args:
             interaction (nextcord.Interaction): Interaction with the command.
         """
+        await interaction.response.defer()
         await update_clan_messages(interaction.guild)
-        await interaction.response.send_message(
+        await interaction.followup.send("Messages have been refreshed.", ephemeral=True)
-            "Messages have been refreshed.", ephemeral=True
-        )