Just to confirm, did you switch your voicemails as seen here https://www.virginmedia.com/help/landline/set-up-landline-voicemail?
Welcome to our community forums and thank you for your first post.
Sorry to hear you are having a similar issue with your voicemail notifications. We can understand this is not ideal and we want to best help. Just to confirm, do you only get this issue on one device? Is this on mobile or landline? If mobile, did you try deleting the voicemail as seen here https://www.virginmedia.com/help/mobile/set-up-virgin-mobile-voicemail ?