MicroStation over usage?

We have received an invoice from Bentley for over usage. Having just checked this it appears that Bentley have reported usage by pc's that don't have MicroStation installed and are just been used (when working from home) to access their work pc via VPN/RDP.

I have asked our Account Manager why this has happened but would like to know if any one else has seen this. 

Bentley - Why is this happening and how do I get the invoice rescinded?