Apple Watch pairing with Apple tv

What type of pairing are you referring to?

Is this about using the remote control functionality? Control Apple TV with Apple Watch - Apple Support

Is this about using Fitness+ on Apple TV? Work out on Apple TV - How to use Apple Fitness+ - Apple Support

What is the model Apple Watch? Identify your Apple Watch - Apple Support

As older models can have a maximum OS version lower than current models, “the latest software” can be ambiguous. Please use actual version numbers.

Unless someone else chimes in with a new idea, I would suggest to contact an expert from the Apple Support staff for further assistance. Contact Apple for support and service (phone numbers) or start your support request online (chat/​email/​callback).