This is yet another common problem with iPhones.
This thread and post may help:
http://community.48months.ie/t5/Need-Help/Personal-Hotspot/m-p/32730#M11084
Let us know how you get on.
Hope this helps.
P.S. between this, iPhone/iMessage/FaceTime activation, roaming problems etc. Apple really seem to go out of their way to make it difficult for people to use their phones on any arbitrary network...
Did that help at all?
Are your internet/APN settings correct?
Does normal internet access work OK?
Double check your settings against the instructions here:
http://community.48months.ie/t5/Need-Help/Internet/m-p/34493#M12560
If they are correct then it's probably an issue with the configuration of the personal hotspot itself.
What exactly goes wrong?
The device that connects to your phone to get internet access stops downloading data?
Describe the problem in more detail please.
What are your hotspot configuration settings - screenshots ideally if possible?
Hope this helps.
Any update?
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