Problem activating own modem (Highest Service Level)

Hi,

I have an old modem (TPLINK TC 7610) which I tried self-activating and landed in a page where I was asked to contact Customer Support. I am currently on Preferred 150 plan and the agent said this modem is listed as Highest Service Level = Preferred 100. So it can't be used.

Now at this moment, there's no such service as Preferred 100. It was upgraded to Preferred 150 few months back by Cox. Agent is asking me to downgrade to 50Mbps if I need to use the modem. The modem has 343Mbps download capability. It's quite evident that the page listing the device was not updated.

Can anyone please give an opinion?

Thanks in advance.