I moved to Oxford in August 2014 for university from Newcastle (where signal has never ever been a problem - always good 4G). However, since moving there my signal and data speeds have been terrible.
Strangely, the city centre is the worst place having never (literally, never) gotten 4G or even a good 3G signal. I almost exclusively get E and GPRS. The rest of Oxford isn't great either. However, if I go to the very west side of Oxford (near the train station) I get good 4G, and heading quite a way East (in Headington) my signal is perfect.
The coverage map shows that Oxford is just about completely covered with 4G however I almost never get it (sadly the one neighbourhood that doesn't have it is where I'll be moving to next month).
I have called O2 and they sent me a new SIM - nothing worked. I went to the Apple Store and they gave me a new iPhone - nothing changed.
What can I do about this? I can probably live without 4G but I what is the point in having a 5GB data allowance when I only really get GPRS in the middle of a city.
While I sympathise with your issue, your only option is to pay off the handset and change network. Until o2 upgrade the masts to cover all Oxford then there is nothing that can be done tyo help i'm afraid.
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