How to cancel credit cards asap

at a costco yesterday I got put into a scary position everyone was yelling next thing I know I'm signing up for a creditcard..... I'm 23 never had one. I work part time sometimes and make 15bucks an hour I told this to the lady and shes like onincome write 30,000 I told her theres no way I make that and she said you're supposed to write an estimate hury up I was freaking out because I felt extremely pressure but wrote that and got the damn card on which they charged my groceries. they said the actual card would take about a week to arrive....
But I dont want it and I feel like a liar and I want to cancel it asap
how do I do that>

thanks for your help in advanced
Asked Jan 28, 2016
call the bank and tell them to cancel it
Answered Jul 28, 2017

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