Beana
You haven't said if the aircraft engines were running. Basically, if they were running then the FA is right to say 'switch it off' as all phones must be switched off when the engines have started.
However, if the engines are off, the FA could have asked the flight crew if it is possible for pax to use their phones.
Most Captains will allow pax to use their phones on the ground when the engines are off and you are experiencing a delay (subject to local airport rules
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