Welcome to the forums and many thanks for your post.
I'm sorry to hear you do not have a splitter cable for your equipment - these are sent with dual packages containing both the TV set top box and broadband hub. I'm guessing the reason this has been missed off is due to only the hub being ordered.
I've been able to locate your account using the details used to register for forums and will request a splitter cable to be sent for you. I'll keep you updated 🙂