Download speeds decreased???

I got Cox internet -preferred 5 years ago. Since then it has increased from $45 a month, to $61 a month.

At first my speeds were low at 1mb download. Even though I am paying for more. Then increased up to 2mbps... But this year it finally increased to over 3mbps.

Now for some reason, and the reason eludes me, I am back to 1mbps.... But I am still paying $61 per month.

It's not my modem, its not my router. It's not my network. It's Cox.

Can someone tell me how/why I can go back down in download/upload speeds. This has actually happened before, but It corrected itself soon after. As of now this has gone on for too long.

It's a little upsetting how you can choose a service, get bad service, then get charged more money for the service that continues to fail. I've been told it's a modem issue, and it's not. Same for router, wall socket connections etc...

Thank you