Amazon Landline issue

Pleas help how to erase my landline number from amazon customer support, because of poor network I called amazon from my landline regarding some issue two days back and i told the guy the registered mobile phone of that account for which i had issue and later i disconnected the call. Now today when I called amazon again from landline for registered mobile of different account they started addressing me with the identity of the account i had called them few days ago. I want to know how would i be able to delete my landline so they dont suspect me. Thankss