If you have connected to a Windscribe server and your IP hasn't changed (for instance when you check on Google "What's my IP"), this could mean two things:

1. You're not actually connected to the VPN because the connection failed (This happens sometimes on the Extension with error "Proxy Failure"). In this case, check if the client is actually connected and the IP changed on it. 

2. The site that detects the IP has cached your IP result, in this case, simply restart the browser and it should show the Windscribe IP instead.