Oh no, it seems the lights on the Christmas tree have gone out! Let's see if we can find the problem and fix it together. First, let's make sure that the fuse isn't blown. If it's not, then we can try changing the bulbs to see if that works. If the bulbs are all working, then we may need to call an electrician to help us troubleshoot the problem. Let's do our best to fix the lights together!