I have recently started using a Samsung S21 5g on O2. I notice that when at a football match everyone around me is able to use their phones a lot of the time, even my friend sitting on my left who is on O2 on an old phone and my son on my right who has a Samsung S21 on Vodafone, I never have a network connection. I usually have 4g signal indicated with 3 or 4 bars showing, I try the signal checker which shows "no network available". I would be grateful for some advice.
