I believe the problems comes from my old ST sim, so I got the new BYOP sim ($16)
probably this works fine for old ST sim, I am not sure...
here are the steps:
1- insert your new sim after you activated using the ST account
2- go to apn.straighttalk.com (this is new) using safari browser(make sure you are using wi-fi) and click on data/apn settings/att&data settings/iPhone/install the profile
reboot the phone.....data is working but the mms is not...
3 Going to Settings > General > Network
Taking the Straight Talk SIM out and putting in a T-Mobile SIM
Go into Cellular Data Network when it shows up
Immediately put the Straight Talk SIM back in
Multitask between Cellular Data Network and the Notes app back and forth until a signal from Straight Talk comes in and the default non-working data & MMS APN are automatically entered.
Once the APNs show up, edit them manually
Cellular Data
APN: att.mvno
Username: *blank*
Password: *blank*
MMS
APN: att.mvno
Username: *blank*
Password: *blank*
MMSC: http://www.mmsc.cingular.com
MMS Proxy: 66.209.11.33
MMS Max Message Size: 1048576
MMS UA Prof URL: *blank*
8. Go toggle Airplane Mode on and off, and reboot the phone
Data and MMS now work fine.
p.s. I am apologize for my English

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