Welcome to the Community Forum and thanks for your post. I'm sorry that you are having problems with your voicemail service on your iPhone 7. Is this working for you now?
Were you able to check your online account to verify that the voicemail is set to On?
If you are still having a problem with this, please let me know and I can check this for you. I'll send you a private message requesting further details. Just check the envelope icon at the top right of this page.
Virgin Media Forum Team
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Have a look on the Internet for iPhone configuration settings, there are a lot that start with * that you can use. I'm sure you will find one to fix this, *#61# will show the current status of forwarding on your phone.
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