Log online users in a discord server

Question

async def log_users():
     while True:
         with open("log.csv", "a") as f:
             f.write(f"{len(client.users)}, {datetime.datetime.now().strftime('%H')}")
             print(f"{len(client.users)}, {datetime.datetime.now().strftime('%H')}")
             await asyncio.sleep(120)

my code looks like this but it returns 0,"hour" even when are many users online