Mobile Device Management

I have had several significant concerns with security on my iPhone. I’d be more than happy to discuss specifics if anyone is interested. Anyways, this question for the community surrounds the setting “VPN & Device Management.” I attempt to sign in and get the attached error message. Generally speaking, it says that someone somewhere is already signed in and I can’t access the service. Does anyone know how I can sign whoever wherever out of that service so I can access it? I have changed the password, signed out of all devices, etc. to no avail. If you have some other solutions, I’d appreciate it. Thank you in advance!