Incorrect biling

In march this year we changed to AT&T to save money. We talked to a rep and was quoted $40.00 for internet and $19.99 for land line phone plus about $5.00 in taxes/fees. The monthly bills since then have been correct on the internet charges, but the landline phone has been wrong. We have been charged $32.00 per month plus taxes for a total $43.01 for the phone alone. I have spoken to several AT&T employees via web talk (I am 81+ years and hard or hearing so calling is not an option) and they all confirmed that I should have received the $19.99 monthly cost plus get a $100.00 Visa card to reimburse for installation cost. Have written many emails and now letters to AT&T head office in Atlanta, but cannot get a reply. 

Does anyone know how to reach an English-speaking rep at ATT&T? The local AT&T rep will not help. Says "it is above my pay grade".

Does anyone know the name of the President of AT&T. His/her email/text?

*****

Any suggestions?

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