Verizon Wireless Added VZ Navigator without my permission Nationwide

Back in March of 2013, my husband upgraded his phone.  I discovered in the fall of 2017 that we had been charged a $4.99 VZ navigator fee each month.  I was telling my son that I was upset over it and the fact that I hadn't noticed it.  He let me know that when he was a salesman for Verizon, that they were told to add this to people's accounts to make a greater profit.  It was done without customers knowing.  I was so mad that Verizon would cheat people.  I called Verizon and they offered me a $15.00 refund which was a joke.  I refused to take it.  Of course, they said I should have been responsible to find the up-charge.  I don't think I should be held responsible when a company is dishonest and charges me for something we did not add to our account.  I would have never know of this dishonest practice Verizon has if my son  hadn't worked for Verizon.  Shame on you Verizon!!!!