Q: system extension cannot be used

I get a message when I start my MacBook Pro :

The system extension “/Library/Frameworks/PrivateTunnel.framework/Versions/Current/Extensions/tun.ke xt” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update.

..

Any advice? My vendor does not have any idea about it.

I am the only "administrator" of this Macbook Pro.

JJ