, I have a second hand galaxy s9 + that I bought two weeks ago, the person who sold me this phone told me that it is unlocked, but now I see that the sim other networks are invalid, and uicc gives me error 407, so I ask for your help to know if I should return this phone to the United States for a refund.
I don't know what to do,please help me
Hi! To unlock the phone, the account information where the device was active for the last time is needed, that is one of the requirements of the Sprint unlock policy. If you have tried the steps in the link SOLUTION: Sprint Hints for Successful Unlocks and your device's still locked, that is when we need the Sprint account information where the device was active for the last time. If you do not have the information, you will need to contact the person that sold you the phone.
Yes, I can verify with the Sprint account information were the device was active for the last time, if you have the Sprint account holder's name or account number. Please visit this link here so you can see all the information to have your device unlocked.
No I don't have these info,I was buy this phone only,without any info,
I told u about verify if the device have a unpaid service,
Uicc don't work in many cases without a problem with payment