Getting 3/4G on that device unfortunately will not happen on our network due to the fact that you need UMTS bands 1700 and 2100 and that phone only has the ability to pickup 900 and 2100 bands. So if you are getting even slow Internet then the APN settings are correct you just don't have the hardware to support our faster data speeds.
As far as the APN settings including for MMS here are the generic ones for an android hopefully they will help but of course we cannot guarantee that it will in fact work, since you already have an APN setup I would recommend just editing the one you already have and make sure it matches.
Hope that helps you at least have more knowledge on the subject, if you have any further questions please let us know.
- Name: T-Mobile Data (or T-Mobile US)
- APN: epc.tmobile.com
- Proxy: <Not set>
- Port: <Not set>
- Username: <Not set>
- Password: <Not set>
- Server: <Not set>
- MMSC: http://mms.msg.eng.t-mobile.com/mms/wapenc
- MMS proxy: <Not set>
- MMS port: <Not set>
- MMS protocol: WAP 2.0
- MCC: 310
- MNC: 260
- Authentication type: <Not set>
- APN type: default,supl,admin,dun,mms
- Note: Using <Not set> instead of the above works if there are no other APNs that conflict.
- Press the Menu key.
- Touch Save.
- Verify that you only have one T-Mobile Data (or T-Mobile US) connection listed.