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S8+ works fine exept in harrogate signal and 4g go haywire phone message says not registerd on net work i do a manual seaech choose vodaphone then it seem to be ok trubble is everytime i go back into harrogate the phone does exact same £70 a month no good
From what you write @meobeou it appears the phone and sim card are ok and it's the signal in Harrogate that's letting things down.
Can you check what is being reported for your postcode in Harrogate via this link > Vodafone status-checker.
As a further process of elimination could you try your sim card in another phone you know that works and see what service you get in Harrogate or ask friends , family and neighbour's what signal they get if there on Vodafone UK.
Also by using the following Vodafone link and copy and pasting the template and answers back here Vodafone can then send this feedback to the networking Department.
A person thinking their Samsung Galaxy Phone maybe at issue can gain help from a Vodafone Highstreet Store to which the process is Repairs or a Samsung Experience Store or Samsung Service Centre.
Current Phone > Samsung Note 20 5G - SM9860 Snapdragon.
Samsung One Ui 2.5 / Android 10.