Current situation. Speedtest produced correct results for my gigabyte plan. Called in to change my services and since then I have only been able to get 25mbps download but correct upload speed. When I call suport they basically reboot the ONT and then decide they need to send a tech to my house, which they won't do for a couple months because of coronavirus.
Asking around online, since my speed locked at 25mbps at the exact same time as I changed my plan, others I have spoken too seem to think my ONT is provisioned incorrectly. How does that happen? It seems to happen a lot if you look online but with computers how does it happen? With computers shouldn't it be pretty much correct all the time?
Try contacting Verizon support through @VerizonSupport on Twitter or the VZ Direct forum at https://www.dslreports.com/forum/vzdirect. They often do a better job then the phone reps. If this can be resolved remotely, they should be able to figure it out.