I am using Softether VPN, VisualSVN and TortoiseSVN to commit and update my projects. The project repositories are in a seperate server.
I configure visualSVN like this:

And this is in SoftetherVPN
Both are using the same certificate. But when I try to update solution from my device, it shows difference certificate so the validation is failed. Please help.


No, most likely they (VisualSVN Server and your VPN/Dynamic DNS) are not using the same certificate.
The certificate used by VisualSVN Server for HTTPS is shown on the Certificate tab, and you need to configure this certificate in VisualSVN Server, not your VPN / Dynamic DNS software. Instructions for configuring the TLS/SSL certificate in VisualSVN Server are given in the article KB134: Configuring SSL Certificates for VisualSVN Server.