Dispute a charge

Hi,

I was on the phone with a helpful rep for an hour on August 19th to help troubleshoot a modem+router that wasn't routing wifi properly.  She escalated the issue after failed attempts to resolve remotely and had a service tech visit our business the following day, August 20th.  The representative explicitly stated that we would not be charged for anything other than a new modem+router, something called a kaleidoscope or something like that that she couldn't provide an exact cost for but sounded like it would likely be under 100 dollars.  When the tech came out, he did not replace our very old modem+router and instead resolved the problem by pressing a button on the existing unit.  Now I'm seeing a charge from yesterday 10/5 for $212.30 .    This is twice what I was expecting to be charged WITH a new modem+router.  I can live with the old modem+router and even a small service fee, but this is beyond the pale. 

As far as our regular bill, it looks like the previous usual charge of 71.95 came out of our account on 9/3.  So it's possible that yesterday's charge included the regular service fee plus fees for this visit.

Thanks for your help,

[Edited: Personal Information]