No Available Callback Options for a Diamond Member

I need to disconnect internet service effective Feb 19, 2026 (end of my billing cycle). The Xfinity Assistant loops and won’t connect me to an agent, and the earliest callback offered is Feb 20. I need the stop-billing date set to Feb 19 so I’m not billed into the next cycle. I have no equipment to return. Please help create the disconnect order and confirm the ETF amount (I've already calculated this based on the contract's language about early termination fees). The "relying on a callback" endless loop using the Xfinity assistant is ridiculous and the fact that the earliest "callback" time is days away is unacceptable. I'm a Diamond Member for over 10 years and this is the only prompt option? I should be able to cancel the service myself in the first place via Mobile. I am moving cross-country in mere days and expected more agency and options in this matter and I am routinely disappointed in Xfinity.