I'm sorry that it's not allowing you to receive the voicemail 1571 feature via the member centre. I've had a look into this and this is because it has already been removed from your account on our side, however the feature has stayed active on our supplier's system. I'm sorry for this error and for any inconvenience caused.
I've placed an order to fully remove voicemail from your line on our supplier's system and this should complete within 72 hours at the latest.
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