iPad failed to send text and email after VPN activation

Uninstall the VPN. Don't just turn it off, remove it completely. They are well known to cause network issues and Apple even provides a Support Article in those cases.

If your device has network connectivity issues, check for VPN and other third-party security software - Apple Support

The only legitimate use is for when required for connecting to a Work or School server and in that case you will be provided with the VPN and Setting to use where troubleshooting is done by the IT department of that location.

Nia MacKay wrote:

My iPad failed to send text and email after I activated VPN

Beyond the networking issues that arise all too often, here is why many of us are skeptical about the benefits and the privacy of the “pinky-promise security” VPNs:

• https://gist.github.com/joepie91/5a9909939e6ce7d09e29#dont-use-vpn-services

Your are welcome!