I have had service with Visible for nearly two years and attempted to upgrade with the new sim a few days ago. I updated the software on my phone and inserted it and signed into the updated Visible app. Then I restarted my phone. I went back to the app and it asked me repeat the steps. I have chatted with 7 live agents. Each agent gets me to the part where a verification code is sent to my phone number via text. Problem is I HAVE NOT been able to receive or make calls, TEXTs or emails since installing the new sim (tried reinstalling old visible sim it no longer works). I have been without service for over two days. I searched google for help and have tried tip like airplane mode, restarting, resetting network options, nothing is working. I can no longer sign into my Visible account. My phone is rendered useless with the exception of current time.
You will have to contact customer service yet again so they can temporarily turn off 2FA so you can get into your account, make sure to tell them you can't receive texts. Surprised they didn't turn it off temporarily when you contacted them.
Try uninstalling the app, restart the phone and download the app again then try to activate again. Not sure I have any other suggestions.