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New Member


5 Messages

Saturday, August 22nd, 2020 6:26 PM

Phone not recognizing simcard

I bought new SIM card on the internet, and activated it in the homepage. but my cell phone doesn't recognize the sim card. I cannot call and cannot get message. 

when I enter the plan Activation Code include my zip code (*123*zipcode*21#), it just said 'error call to service center'... I called to service center!!!! The robot checked your sim card is already activated. I wanted to call with person, NOT robot. 


When I put my SIM card in my phone and turned it on, and it told me to enter new wireless number. I should have written down my new wireless number, but I put another one. I think that's the reason of the problem. How can I solve the problem? 

Accepted Solution

Official Solution

Community Support


224.9K Messages

3 years ago

Hello, @Yoojin,


Thank you for reaching out. For help in activating the new SIM card, please go by your neighborhood AT&T Store.


Have a great week.


James, AT&T Community Specialist

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