Plan changed and upgraded without my consent

I randomly logged in one day and saw that my internet got upgraded and changed without my consent. I chatted in multiple times and was reassured it would get fixed. They opened two tickets for me. I have gotten zero communication throughout the whole process and have had to consistently call them. They closed my ticket and stated that I made the change. They cannot provide evidence of the change. Zero confirmation emails or order. Nothing on my end. Only a login on their end that I cannot see. I feel like they are trying to make me pay for this upgraded service. I was on the 400 mbps plan, suddenly that doesn’t exist anymore. I had a promotion until October 2026 that’s gone. And now my bill went from $35 to $70. They are refusing to resolve my issue and are making me pay for a change I did not make. It’s very maddening and disappointing. I’ve been reassured it would get fixed and they closed the ticket and denied my request to speak to a supervisor.