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If this was happening to me then my choice of action would be to phone 191 and ask them to access my account and give it a look over.
Live Chat can help you too.
Just for peace of mind if nothing else.
You may find it could be a glitch by Vodafones systems or the codes are getting stuck in the system.
Current Phone > Samsung Note 9 _512Gb > Model: SM-N960 Hybrid-Duos.
Samsung One Ui / Pie.
Samsung Gear s3 Frontier Watch.