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[Android Central Question]

I brought my mum a used phone 6 months ago and it is no longer accepting her
Vodafone sim card it was originally with Telstra but will accept my optus sim card with no issues her sim card works in my phone tho. 1 phone store said it had been blacklisted but when I did an imei check it says it is clean how can i get her aim card to work again

 

[B. Diddy]

Welcome to Android Central! Did you try contacting both Telstra and Vodafone directly to ask if the IMEI has been blacklisted?