Not getting 100Mpbs Upload

Originally, we upgraded the internet a while ago to get 1 Gigabyte with 35 upload speed. We called yesterday 3/21/2026 because we realized we don't need cable; we don't even use it due to the apps and streaming services. But they made this offer. 1.2 Gig, with 100mbps upload. Can't say no to that, of course. I checked my upload speed it's at 41.  I called and spoke to a lady for an hour yesterday then she said someone will be out at 2pm the following day. She then called the day of (3/22/2026) to say it should be fixed no worker needed so we checked it while on the phone with her and still 41 upload speed.  So, at this point we ask to speak to a supervisor, but they said no-one was available they will call me back in 30 mins.  Which I doubt.  I'm a Computer Science Major, the upload speed from 35 to 100  mpbs was the only reason I took the promotion.  I have a XB7 modem so it should be capable.  But honestly, I feel like they lied to sell a   promotion