Machine Cert Authentication Fails when there are multiple certs

I am making a remote access VPN with two factor Authentication

1) Machine cert checker 2) LOgin Credentials

Machine Cert checker is like this:

When there are multiple certs in CurrentUser store (Searches in HKEY_CURRENT_USER for the machine) it will not work and fallback can anyone help me to resolve this issue ?

It works well when there is only one cert.