Why can’t I update my phone?

Whenever I try updating my phone, it says “Unable to Verify Update” due to “no longer [being connected to] the internet.” I looked up on Google what I should do when that happens and it just says to delete the data and reinstall it and then it should work but I’ve done that multiple times and it still tells me the same thing. (Also side note, yes I’m connected to the internet, I’ve tried turning my phone off and back on, etc.) Please help, this is getting very annoying and I just want to update my phone.