Why won't my visual voicemail work?

[Android Central Question]

I just bought a new lg stylo 3 plus and it didn't come with a visual voicemail though I'm paying for the service. I downloaded the same visual voicemail program that I had with the stylo 2 and it keeps giving me an error message, "can't connect to the to the mobile network, check data settings" which I did. I'm at a loss, any suggestions?