For years my bill has been $19.99 per month. Now I am being told that my charge is $40 a month. How did this
happen? I really believe I am being overcharged.
You should contact billing by phone. We are not going to be able to see your account and you should give your account information to somebody on the phone rather than online.
I would venture a guess that your contract and/or discount may have expired. You can view your bill(s) on myverizon.com and find out what changed (accounts and services - Bill and payment - drop down menu should be current by default).
BTW if FIOS is available in your area you may be able to switch to the 3/1 Mb/s plan for a similar price (40), but you need to call CS.