I had a similar issue in the past, and I got over it by doing some cleaning in my database. It turns out that you need to remove orphan dabatase records from uninstalled plugins once in a while to avoid such bugs. Search for “db optimize” at the plugins repository and let us know if it worked out for you.
VPN services also have problem. I used something better which is more powerful but no success. Maybe because it rely on IP. I don’t know I’m not good in network stuff.