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Can you not connect to Mobile Network Data anywhere or is it in one area.
i.e at home.
Can you please try rebooting your phone by turning Aireplane Mode On and Off.
Manually choosing another Network in your phones settings ,and then re choose Vodafone can help.
Can you try your Sim Card in another phone as a process of elimination to rule out the phone or sim card that may be at fault. Try another Sim in your phone.
If necessary any Vodafone Shop can replace the Sim Card via a Sim Swap.