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Please see here: How do I book a device in for repair?
However, I don't think the information on the link is up to date and there is further information here but the service dones not seem to be available Device help and Repair . You should be able to take the phone into a Vodafone Store where the fault will be looked and the phone sent off to the Repair Centre. You will have a 24 month warranty on the device, if there is any charge the store will let you know.
edited to add: Before you send the phone for repair or take the phone into a store, make sure you have backed up your contents, removed the SIM and SD card (if applicable) . To protect your personal information it is also a good idea to factory reset the phone, you can quickly restore from back up when the phone has been repaired.
Do you have any idea on how the issue started ?
What's happening ?
Check with a torch to see if there is any debris in there causing possible issues.
If this is a result from an accidental bump or water damage then the 24 month manufacturing warranty wouldn't apply.
Possibly household contents insurance and some bank accounts provide cover as a perk of the account etc may come into force.
Before surrendering the phone take time and date stamped pictures of the phone with one of it turned On and one of any visible water indicators to show it's aesthetic condition just in case.
Make sure the Vodafone Highstreet Store Staff makes notes of the phone's condition on their systems before it's sent off.
I wish you all the best with this situation.
🌈Stay Safe & Stay Alert. 🌈
Current Phone > Samsung Note 10+ 5G
Samsung One Ui 2.5 / Android 10.
Thank you for advice. After two days (and three different advisors) of trying to get a chat time booked in and sustained with vodafone I have now been told they wil collect it and repair it for me. I have taken out cards but battery is flat due to not charging so can do no more with it. My contacts are on the sim. I await developments!