I had recently performed DNS and IP leak tests and it was seen that the test sites were able to see
MY REAL IP, ISP and even my Location.
In Stealth mode I had MASK MY IP and CUSTOM IP ADDRESS feature ON the whole time.
i don't recommend such vpns which even doesn't able to protect you from all issues. Would recommend you to go for a good vpn service which provides secure connection and and protects your IP and dns from leaking.. do run the ip leak test at first when you purchase a vpn service. Also, for more detailed info about leaks and how to run proper test and how to check leaks then i would recommend you one of the best article that i followed few months back when i was in your position https://www.purevpn.com/blog/is-your-vpn-leaking-your-ip-address/
Have a great day buddy!