I have a 5G device with 5G sim, it works very well in 5G areas but where i live in Chester 4G is available and it is becoming poorer and poorer with respect to all functions, telephone call, media. it is becoming a real problem that if it cannot improve i will have to leave O2 to another faster provider. A 4G speed test download is 0.53 mbps
Check it on 3g as it may be much faster.
No option but to move to a better network then @Stuart8
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