had the plan price change three times including a 40$ increase on the last month of the term.
A subscriber's plan price will only increase if/when a promotional or special discount ends. At no other time does a subscriber's plan price increase.
The monthly bill can increase due to the aforementioned discounts ending and/or state/local taxes increasing.
If you're having speed issues outside of normal evening congestion and/or plan data exhaustion and you would like help, please start a new topic in Tech Support concerning such.