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Vodafone on 191 or Live Chat themselves can imei block it so no one can use it and cancel the sim card.
They'll then send you out a new sim Card.
Before it will work you may need to call Vodafone again to have the account bar lifted.
Also https://support.google.com/accounts/answer. might help.
Current Phone > Samsung Note 9 _512Gb > Model: SM-N960 Hybrid-Duos.
Samsung Gear s3 Frontier Watch.
What @BandOfBrothers has suggested will stop the SIM being used, but your Google account will still be on the phone. You can remove that remotely by signing into your Google account on a pc. Go to Account, then Security and Devices. Under Manage Device, there's the option to remove account access. If you find the phone again, you'll need to sign in, but I don't know whether you'll also need to set everythign up from scratch.
If the device is permanently lost, you can get a replacement SIM. Activate this and the old one will cease to work.